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• APA Referencing (7th Ed.) Quick Guide | In-text Citations & References

APA Referencing (7th Ed.) Quick Guide | In-text Citations & References

Published on 18 January 2021 by Raimo Streefkerk . Revised on 17 January 2024.

This citation guide outlines the most important citation guidelines from the 7th edition APA Publication Manual (2020). Scribbr also offers free guides for the older APA 6th edition , MLA Style , and Chicago Style .

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Table of contents

Apa in-text citations, apa references, formatting the apa reference page, free lecture slides.

In-text citations are brief references in the running text that direct readers to the reference entry at the end of the paper. You include them every time you quote or paraphrase someone else’s ideas or words.

An APA in-text citation consists of the author’s last name and the year of publication (also known as the author-date system). If you’re citing a specific part of a source, you should also include a locator such as a page number or timestamp. For example: (Smith, 2020, p. 170) .

Parenthetical vs. narrative citation

The in-text citation can take two forms: parenthetical and narrative. Both types are generated automatically when citing a source with Scribbr’s APA Citation Generator.

• Parenthetical citation: According to new research … (Smith, 2020) .
• Narrative citation: Smith (2020) notes that …

Multiple authors and corporate authors

The in-text citation changes slightly when a source has multiple authors or an organization as an author. Pay attention to punctuation and the use of the ampersand (&) symbol.

Missing information

When the author, publication date or locator is unknown, take the steps outlined below.

Prevent plagiarism, run a free check.

APA references generally include information about the author , publication date , title , and source . Depending on the type of source, you may have to include extra information that helps your reader locate the source.

Reference examples

Citing a source starts with choosing the correct reference format. Use Scribbr’s Citation Example Generator to learn more about the format for the most common source types. Pay close attention to punctuation, capitalization, and italicization.

Generate APA citations for free

It is not uncommon for certain information to be unknown or missing, especially with sources found online. In these cases, the reference is slightly adjusted.

On the first line of the page, write the section label “References” (in bold and centred). On the second line, start listing your references in alphabetical order .

Apply these formatting guidelines to the APA reference page:

• Double spacing (within and between references)
• Hanging indent of ½ inch
• Legible font (e.g. Times New Roman 12 or Arial 11)
• Page number in the top-right header

Which sources to include

On the reference page, you only include sources that you have cited in the text (with an in-text citation ). You should not include references to personal communications that your reader can’t access (e.g. emails, phone conversations or private online material).

Are you a teacher or professor looking to introduce your students to APA Style? Download our free introductory lecture slides, available for Google Slides and Microsoft PowerPoint.

Open Google Slides Download PowerPoint

Cite this Scribbr article

If you want to cite this source, you can copy and paste the citation or click the ‘Cite this Scribbr article’ button to automatically add the citation to our free Reference Generator.

Streefkerk, R. (2024, January 17). APA Referencing (7th Ed.) Quick Guide | In-text Citations & References. Scribbr. Retrieved 14 May 2024, from https://www.scribbr.co.uk/referencing/apa-style/

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How to Cite a Research Paper in APA

Last Updated: October 19, 2022 Fact Checked

This article was co-authored by wikiHow Staff . Our trained team of editors and researchers validate articles for accuracy and comprehensiveness. wikiHow's Content Management Team carefully monitors the work from our editorial staff to ensure that each article is backed by trusted research and meets our high quality standards. There are 12 references cited in this article, which can be found at the bottom of the page. This article has been fact-checked, ensuring the accuracy of any cited facts and confirming the authority of its sources. This article has been viewed 160,136 times. Learn more...

If you’re citing a research article or paper in APA style, you’ll need to use a specific citation format that varies depending on the source. Assess whether your source is an article or report published in an academic journal or book, or whether it is an unpublished research paper, such as a print-only thesis or dissertation. Either way, your in-text citations will need to include information about the author (if available) and the date when your source was published or written.

Sample Citations

Writing an In-Text Citation

• For example, you may write, “Gardener (2008) notes, ‘There are several factors to consider about lobsters’ (p. 199).”

• For example, you may write, “‘There are several factors to consider about lobsters’ (Gardner, 2008, p. 199).” Or, “The paper claims, ‘The fallen angel trope is common in religious and non-religious texts’ (Meek & Hill, 2015, p.13-14).”
• For articles with 3-5 authors, write out the names of all the authors the first time you cite the source. For example: (Hammett, Wooster, Smith, & Charles, 1928). In subsequent citations, write only the first author’s name, followed by et al.: (Hammett et al., 1928).
• If there are 6 or more authors for the paper, include the last name of the first author listed and then write "et al." to indicate that there are more than 5 authors.
• For example, you may write, "'This is a quote' (Minaj et al., 1997, p. 45)."

• For example, you may write, “‘The risk of cervical cancer in women is rising’ (American Cancer Society, 2012, p. 2).”

• For example, you may write, “‘Shakespeare may have been a woman’ (“Radical English Literature,” 2004, p. 45).” Or, “The paper notes, ‘There is a boom in Virgin Mary imagery’ (“Art History in Italy,” 2011, p. 32).”

• For example, you may write, “‘There are several factors to consider about lobsters’ (Gardner, 2008, p. 199).” Or, “The paper claims, ‘The fallen angel trope is common in religious and non-religious texts’ (“Iconography in Italian Frescos,” 2015, p.13-14).”

• For example, you may write, “‘There are several factors to consider about lobsters’ (Gardner, 2008, p. 199).” Or, “The paper claims, ‘The fallen angel trope is common in religious and non-religious texts’ (“Iconography in Italian Frescos,” 2015, p.145-146).”

• For example, you may write, “‘The effects of food deprivation are long-term’ (Mett, 2005, para. 18).”

Creating a Reference List Citation for a Published Source

• Material on websites is also considered “published,” even if it’s not peer-reviewed or associated with a formal publishing company.
• While academic dissertations or theses that are print-only are considered unpublished, these types of documents are considered published if they’re included in an online database (such as ProQuest) or incorporated into an institutional repository.

• For example, you may write, “Gardner, L. M.” Or, “Meek, P. Q., Kendrick, L. H., & Hill, R. W.”
• If there is no author, you can list the name of the organization that published the research paper. For example, you may write, “American Cancer Society” or “The Reading Room.”
• Formally published documents that don’t list an author or that have a corporate author are typically reports or white papers .

• For example, you may write, “Gardner, L. M. (2008).” Or, “American Cancer Society. (2015).”

• For example, you may write, “Gardner, L. M. (2008). Crustaceans: Research and data.” Or, “American Cancer Society. (2015). Cervical cancer rates in women ages 20-45.”

• For example, for a journal article, you may write, “Gardner, L. M. (2008). Crustaceans: Research and data. Modern Journal of Malacostracan Research, 25, 150-305.”
• For a book chapter, you could write: “Wooster, B. W. (1937). A comparative study of modern Dutch cow creamers. In T. E. Travers (Ed.), A Detailed History of Tea Serviceware (pp. 127-155). London: Wimble Press."

• For example, you may write, “Kotb, M. A., Kamal, A. M., Aldossary, N. M., & Bedewi, M. A. (2019). Effect of vitamin D replacement on depression in multiple sclerosis patients. Multiple Sclerosis and Related Disorders, 29, 111-117. Retrieved from PubMed, https://www.ncbi.nlm.nih.gov/pubmed/30708308.
• If you’re citing a paper or article that was published online but did not come from an academic journal or database, provide information about the author (if known), the date of publication (if available), and the website where you found the article. For example: “Hill, M. (n.d.). Egypt in the Ptolemaic Period. Retrieved from https://www.metmuseum.org/toah/hd/ptol/hd_ptol.htm”

Citing Unpublished Sources in Your Reference List

• Print-only dissertations or theses.
• Articles or book chapters that are in press or have been recently prepared or submitted for publication.
• Papers that have been rejected for publication or were never intended for publication (such as student research papers or unpublished conference papers).

• If the paper is currently being prepared for publication, include the author’s name, the year when the current draft was completed, and the title of the article in italics, followed by “Manuscript in preparation.” For example: Wooster, B. W. (1932). What the well-dressed man is wearing. Manuscript in preparation.
• If the paper has been submitted for publication, format the citation the same way as if it were in preparation, but instead follow the title with “Manuscript submitted for publication.” For example: Wooster, B. W. (1932). What the well-dressed man is wearing. Manuscript submitted for publication.
• If the paper has been accepted for publication but is not yet published, replace the date with “in press.” Do not italicize the paper title, but do include the title of the periodical or book in which it will be published and italicize that. For example: Wooster, B. W. (in press). What the well-dressed man is wearing. Milady’s Boudoir.

• If the paper was written for a conference but never published, your citation should look like this: Riker, W. T. (2019, March). Traditional methods for the preparation of spiny lobe-fish. Paper presented at the 325th Annual Intergalactic Culinary Conference, San Francisco, CA.
• For an unpublished paper written by a student for a class, include details about the institution where the paper was written. For example: Crusher, B. H. (2019). A typology of Cardassian skin diseases. Unpublished manuscript, Department of External Medicine, Starfleet Academy, San Francisco, CA.

• For example, you may write, “Pendlebottom, R. H. (2011). Iconography in Italian Frescos (Unpublished doctoral dissertation). New York University, New York, United States.”

Community Q&A

• If you want certain information to stand out in the research paper, then you can consider using a block quote. Thanks Helpful 0 Not Helpful 0

You Might Also Like

• ↑ https://libraryguides.vu.edu.au/apa-referencing/7JournalArticles
• ↑ https://owl.purdue.edu/owl/research_and_citation/apa_style/apa_formatting_and_style_guide/in_text_citations_author_authors.html
• ↑ https://bowvalleycollege.libguides.com/c.php?g=714519&p=5093747
• ↑ https://guides.libraries.psu.edu/apaquickguide/intext
• ↑ https://owl.purdue.edu/owl/research_and_citation/apa_style/apa_formatting_and_style_guide/in_text_citations_the_basics.html
• ↑ https://libguides.southernct.edu/c.php?g=7125&p=34582#1951239
• ↑ https://owl.purdue.edu/owl/research_and_citation/apa_style/apa_formatting_and_style_guide/reference_list_electronic_sources.html
• ↑ https://owl.purdue.edu/owl/research_and_citation/apa_style/apa_formatting_and_style_guide/reference_list_articles_in_periodicals.html
• ↑ https://owl.purdue.edu/owl/research_and_citation/apa_style/apa_formatting_and_style_guide/reference_list_books.html
• ↑ https://morlingcollege.libguides.com/apareferencing/unpublished-or-informally-published-work
• ↑ https://owl.purdue.edu/owl/research_and_citation/apa_style/apa_formatting_and_style_guide/general_apa_faqs.html
• ↑ https://owl.purdue.edu/owl/research_and_citation/apa_style/apa_formatting_and_style_guide/reference_list_other_print_sources.html

About This Article

To cite a research paper in-text in APA, name the author in the text to introduce the quote and put the publication date for the text in parentheses. At the end of your quote, put the page number in parentheses. If you don’t mention the author in your prose, include them in the citation. Start the citation, which should come at the end of the quote, by listing the author’s last name, the year of publication, and the page number. Make sure to put all of this information in parentheses. If there’s no author, use the name of the organization that published the paper or the first few words from the title. To learn how to cite published and unpublished sources in your reference list, keep reading! Did this summary help you? Yes No

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APA Style (7th Edition) Citation Guide: Introduction

• Introduction
• Journal Articles
• Magazine/Newspaper Articles
• Books & Ebooks
• Government & Legal Documents
• Biblical Sources
• Secondary Sources
• Films/Videos/TV Shows
• How to Cite: Other
• Additional Help

Who Should Use APA Style?

APA style is used by social science disciplines such as communication studies, economics, education, psychology, and sociology; it is also used by business and nursing.

What is APA Style?

APA style, created by the American Psychological Association, is a set of rules for formatting manuscripts, including research papers.

In APA, you must cite sources that you have paraphrased, quoted or otherwise used to write your research paper. Cite your sources in two places:

• In the body of your paper where you add a brief in-text citation .
• In the References list at the end of your paper where you give more complete information for the source.
• APA 7th ed. Sample Paper
• APA Style Paper template (Microsoft Word)
• APA 7th. ed. Journal Article Reference Checklist
• APA 7th. ed. Student Paper Checklist

APA Style Guide (7th Edition)

Four Elements of a Reference

A reference generally has these four elements: author, date, title, and source. Each element answers a question and is listed in your citation in the following order:

• author : Who is responsible for this work?
• date : When was this work published?
• title : What is the work called?
• source : Where can I retrieve this work?

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Reference List: Common Reference List Examples

Article (with doi).

Alvarez, E., & Tippins, S. (2019). Socialization agents that Puerto Rican college students use to make financial decisions. Journal of Social Change , 11 (1), 75–85. https://doi.org/10.5590/JOSC.2019.11.1.07

Laplante, J. P., & Nolin, C. (2014). Consultas and socially responsible investing in Guatemala: A case study examining Maya perspectives on the Indigenous right to free, prior, and informed consent. Society & Natural Resources , 27 , 231–248. https://doi.org/10.1080/08941920.2013.861554

Use the DOI number for the source whenever one is available. DOI stands for "digital object identifier," a number specific to the article that can help others locate the source. In APA 7, format the DOI as a web address. Active hyperlinks for DOIs and URLs should be used for documents meant for screen reading. Present these hyperlinks in blue and underlined text (the default formatting in Microsoft Word), although plain black text is also acceptable. Be consistent in your formatting choice for DOIs and URLs throughout your reference list. Also see our Quick Answer FAQ, "Can I use the DOI format provided by library databases?"

Jerrentrup, A., Mueller, T., Glowalla, U., Herder, M., Henrichs, N., Neubauer, A., & Schaefer, J. R. (2018). Teaching medicine with the help of “Dr. House.” PLoS ONE , 13 (3), Article e0193972. https://doi.org/10.1371/journal.pone.0193972

For journal articles that are assigned article numbers rather than page ranges, include the article number in place of the page range.

For more on citing electronic resources, see  Electronic Sources References .

Article (Without DOI)

Found in a common academic research database or in print.

Casler , T. (2020). Improving the graduate nursing experience through support on a social media platform. MEDSURG Nursing , 29 (2), 83–87.

If an article does not have a DOI and you retrieved it from a common academic research database through the university library, there is no need to include any additional electronic retrieval information. The reference list entry looks like the entry for a print copy of the article. (This format differs from APA 6 guidelines that recommended including the URL of a journal's homepage when the DOI was not available.) Note that APA 7 has additional guidance on reference list entries for articles found only in specific databases or archives such as Cochrane Database of Systematic Reviews, UpToDate, ProQuest Dissertations and Theses Global, and university archives. See APA 7, Section 9.30 for more information.

Found on an Open Access Website

Eaton, T. V., & Akers, M. D. (2007). Whistleblowing and good governance. CPA Journal , 77 (6), 66–71. http://archives.cpajournal.com/2007/607/essentials/p58.htm

Provide the direct web address/URL to a journal article found on the open web, often on an open access journal's website. In APA 7, active hyperlinks for DOIs and URLs should be used for documents meant for screen reading. Present these hyperlinks in blue and underlined text (the default formatting in Microsoft Word), although plain black text is also acceptable. Be consistent in your formatting choice for DOIs and URLs throughout your reference list.

Weinstein, J. A. (2010).  Social change  (3rd ed.). Rowman & Littlefield.

If the book has an edition number, include it in parentheses after the title of the book. If the book does not list any edition information, do not include an edition number. The edition number is not italicized.

American Nurses Association. (2015). Nursing: Scope and standards of practice (3rd ed.).

If the author and publisher are the same, only include the author in its regular place and omit the publisher.

Lencioni, P. (2012). The advantage: Why organizational health trumps everything else in business . Jossey-Bass. https://amzn.to/343XPSJ

As a change from APA 6 to APA 7, it is no longer necessary to include the ebook format in the title. However, if you listened to an audiobook and the content differs from the text version (e.g., abridged content) or your discussion highlights elements of the audiobook (e.g., narrator's performance), then note that it is an audiobook in the title element in brackets. For ebooks and online audiobooks, also include the DOI number (if available) or nondatabase URL but leave out the electronic retrieval element if the ebook was found in a common academic research database, as with journal articles. APA 7 allows for the shortening of long DOIs and URLs, as shown in this example. See APA 7, Section 9.36 for more information.

Chapter in an Edited Book

Poe, M. (2017). Reframing race in teaching writing across the curriculum. In F. Condon & V. A. Young (Eds.), Performing antiracist pedagogy in rhetoric, writing, and communication (pp. 87–105). University Press of Colorado.

Include the page numbers of the chapter in parentheses after the book title.

Christensen, L. (2001). For my people: Celebrating community through poetry. In B. Bigelow, B. Harvey, S. Karp, & L. Miller (Eds.), Rethinking our classrooms: Teaching for equity and justice (Vol. 2, pp. 16–17). Rethinking Schools.

Also include the volume number or edition number in the parenthetical information after the book title when relevant.

Freud, S. (1961). The ego and the id. In J. Strachey (Ed.),  The standard edition of the complete psychological works of Sigmund Freud  (Vol. 19, pp. 3-66). Hogarth Press. (Original work published 1923)

When a text has been republished as part of an anthology collection, after the author’s name include the date of the version that was read. At the end of the entry, place the date of the original publication inside parenthesis along with the note “original work published.” For in-text citations of republished work, use both dates in the parenthetical citation, original date first with a slash separating the years, as in this example: Freud (1923/1961). For more information on reprinted or republished works, see APA 7, Sections 9.40-9.41.

Classroom Resources

Citing classroom resources.

If you need to cite content found in your online classroom, use the author (if there is one listed), the year of publication (if available), the title of the document, and the main URL of Walden classrooms. For example, you are citing study notes titled "Health Effects of Exposure to Forest Fires," but you do not know the author's name, your reference entry will look like this:

Health effects of exposure to forest fires [Lecture notes]. (2005). Walden University Canvas. https://waldenu.instructure.com

If you do know the author of the document, your reference will look like this:

Smith, A. (2005). Health effects of exposure to forest fires [PowerPoint slides]. Walden University Canvas. https://waldenu.instructure.com  

A few notes on citing course materials:

• [Lecture notes]
• [Course handout]
• [Study notes]
• It can be difficult to determine authorship of classroom documents. If an author is listed on the document, use that. If the resource is clearly a product of Walden (such as the course-based videos), use Walden University as the author. If you are unsure or if no author is indicated, place the title in the author spot, as above.
• If you cannot determine a date of publication, you can use n.d. (for "no date") in place of the year.

Note:  The web location for Walden course materials is not directly retrievable without a password, and therefore, following APA guidelines, use the main URL for the class sites: https://class.waldenu.edu.

Citing Tempo Classroom Resources

Clear author: 

Smith, A. (2005). Health effects of exposure to forest fires [PowerPoint slides]. Walden University Brightspace. https://mytempo.waldenu.edu

Unclear author:

Health effects of exposure to forest fires [Lecture notes]. (2005). Walden University Brightspace. https://mytempo.waldenu.edu

Conference Sessions and Presentations

Feinman, Y. (2018, July 27). Alternative to proctoring in introductory statistics community college courses [Poster presentation]. Walden University Research Symposium, Minneapolis, MN, United States. https://scholarworks.waldenu.edu/symposium2018/23/

Torgerson, K., Parrill, J., & Haas, A. (2019, April 5-9). Tutoring strategies for online students [Conference session]. The Higher Learning Commission Annual Conference, Chicago, IL, United States. http://onlinewritingcenters.org/scholarship/torgerson-parrill-haas-2019/

Dictionary Entry

Merriam-Webster. (n.d.). Leadership. In Merriam-Webster.com dictionary . Retrieved May 28, 2020, from https://www.merriam-webster.com/dictionary/leadership

When constructing a reference for an entry in a dictionary or other reference work that has no byline (i.e., no named individual authors), use the name of the group—the institution, company, or organization—as author (e.g., Merriam Webster, American Psychological Association, etc.). The name of the entry goes in the title position, followed by "In" and the italicized name of the reference work (e.g., Merriam-Webster.com dictionary , APA dictionary of psychology ). In this instance, APA 7 recommends including a retrieval date as well for this online source since the contents of the page change over time. End the reference entry with the specific URL for the defined word.

Discussion Board Post

Osborne, C. S. (2010, June 29). Re: Environmental responsibility [Discussion post]. Walden University Canvas.  https://waldenu.instructure.com  

Dissertations or Theses

Retrieved From a Database

Nalumango, K. (2019). Perceptions about the asylum-seeking process in the United States after 9/11 (Publication No. 13879844) [Doctoral dissertation, Walden University]. ProQuest Dissertations and Theses.

Retrieved From an Institutional or Personal Website

Evener. J. (2018). Organizational learning in libraries at for-profit colleges and universities [Doctoral dissertation, Walden University]. ScholarWorks. https://scholarworks.waldenu.edu/cgi/viewcontent.cgi?article=6606&context=dissertations

Unpublished Dissertation or Thesis

Kirwan, J. G. (2005). An experimental study of the effects of small-group, face-to-face facilitated dialogues on the development of self-actualization levels: A movement towards fully functional persons [Unpublished doctoral dissertation]. Saybrook Graduate School and Research Center.

For further examples and information, see APA 7, Section 10.6.

Legal Material

For legal references, APA follows the recommendations of The Bluebook: A Uniform System of Citation , so if you have any questions beyond the examples provided in APA, seek out that resource as well.

Court Decisions

Reference format:

Name v. Name, Volume Reporter Page (Court Date). URL

Sample reference entry:

Brown v. Board of Education, 347 U.S. 483 (1954). https://www.oyez.org/cases/1940-1955/347us483

Sample citation:

In Brown v. Board of Education (1954), the Supreme Court ruled racial segregation in schools unconstitutional.

Note: Italicize the case name when it appears in the text of your paper.

Name of Act, Title Source § Section Number (Year). URL

Sample reference entry for a federal statute:

Individuals With Disabilities Education Act, 20 U.S.C. § 1400 et seq. (2004). https://www.congress.gov/108/plaws/publ446/PLAW-108publ446.pdf

Sample reference entry for a state statute:

Minnesota Nurse Practice Act, Minn. Stat. §§ 148.171 et seq. (2019). https://www.revisor.mn.gov/statutes/cite/148.171

Sample citation: Minnesota nurses must maintain current registration in order to practice (Minnesota Nurse Practice Act, 2010).

Note: The § symbol stands for "section." Use §§ for sections (plural). To find this symbol in Microsoft Word, go to "Insert" and click on Symbol." Look in the Latin 1-Supplement subset. Note: U.S.C. stands for "United States Code." Note: The Latin abbreviation " et seq. " means "and what follows" and is used when the act includes the cited section and ones that follow. Note: List the chapter first followed by the section or range of sections.

Unenacted Bills and Resolutions

(Those that did not pass and become law)

Title [if there is one], bill or resolution number, xxx Cong. (year). URL

Sample reference entry for Senate bill:

Anti-Phishing Act, S. 472, 109th Cong. (2005). https://www.congress.gov/bill/109th-congress/senate-bill/472

Sample reference entry for House of Representatives resolution:

Anti-Phishing Act, H.R. 1099, 109th Cong. (2005). https://www.congress.gov/bill/109th-congress/house-bill/1099

The Anti-Phishing Act (2005) proposed up to 5 years prison time for people running Internet scams.

These are the three legal areas you may be most apt to cite in your scholarly work. For more examples and explanation, see APA 7, Chapter 11.

Magazine Article

Clay, R. (2008, June). Science vs. ideology: Psychologists fight back about the misuse of research. Monitor on Psychology , 39 (6). https://www.apa.org/monitor/2008/06/ideology

Note that for citations, include only the year: Clay (2008). For magazine articles retrieved from a common academic research database, leave out the URL. For magazine articles from an online news website that is not an online version of a print magazine, follow the format for a webpage reference list entry.

Newspaper Article (Retrieved Online)

Baker, A. (2014, May 7). Connecticut students show gains in national tests. New York Times . http://www.nytimes.com/2014/05/08/nyregion/national-assessment-of-educational-progress-results-in-Connecticut-and-New-Jersey.html

Include the full date in the format Year, Month Day. Do not include a retrieval date for periodical sources found on websites. Note that for citations, include only the year: Baker (2014). For newspaper articles retrieved from a common academic research database, leave out the URL. For newspaper articles from an online news website that is not an online version of a print newspaper, follow the format for a webpage reference list entry.

OASIS Resources

Oasis webpage.

OASIS. (n.d.). Common reference list examples . Walden University. https://academicguides.waldenu.edu/writingcenter/apa/references/examples

For all OASIS content, list OASIS as the author. Because OASIS webpages do not include publication dates, use “n.d.” for the year.

Interactive Guide

OASIS. (n.d.). Embrace iterative research and writing [Interactive guide]. Walden University. https://academics.waldenu.edu/oasis/iterative-research-writing-web

For OASIS multimedia resources, such as interactive guides, include a description of the resource in brackets after the title.

Online Video/Webcast

Walden University. (2013).  An overview of learning  [Video]. Walden University Canvas.  https://waldenu.instructure.com  

Use this format for online videos such as Walden videos in classrooms. Most of our classroom videos are produced by Walden University, which will be listed as the author in your reference and citation. Note: Some examples of audiovisual materials in the APA manual show the word “Producer” in parentheses after the producer/author area. In consultation with the editors of the APA manual, we have determined that parenthetical is not necessary for the videos in our courses. The manual itself is unclear on the matter, however, so either approach should be accepted. Note that the speaker in the video does not appear in the reference list entry, but you may want to mention that person in your text. For instance, if you are viewing a video where Tobias Ball is the speaker, you might write the following: Tobias Ball stated that APA guidelines ensure a consistent presentation of information in student papers (Walden University, 2013). For more information on citing the speaker in a video, see our page on Common Citation Errors .

Taylor, R. [taylorphd07]. (2014, February 27). Scales of measurement [Video]. YouTube. https://www.youtube.com/watch?v=PDsMUlexaMY

OASIS. (2020, April 15). One-way ANCOVA: Introduction [Video]. YouTube. https://youtu.be/_XnNDQ5CNW8

For videos from streaming sites, use the person or organization who uploaded the video in the author space to ensure retrievability, whether or not that person is the speaker in the video. A username can be provided in square brackets. As a change from APA 6 to APA 7, include the publisher after the title, and do not use "Retrieved from" before the URL. See APA 7, Section 10.12 for more information and examples.

See also reference list entry formats for TED Talks .

Technical and Research Reports

Edwards, C. (2015). Lighting levels for isolated intersections: Leading to safety improvements (Report No. MnDOT 2015-05). Center for Transportation Studies. http://www.cts.umn.edu/Publications/ResearchReports/reportdetail.html?id=2402

Technical and research reports by governmental agencies and other research institutions usually follow a different publication process than scholarly, peer-reviewed journals. However, they present original research and are often useful for research papers. Sometimes, researchers refer to these types of reports as gray literature , and white papers are a type of this literature. See APA 7, Section 10.4 for more information.

Reference list entires for TED Talks follow the usual guidelines for multimedia content found online. There are two common places to find TED talks online, with slightly different reference list entry formats for each.

TED Talk on the TED website

If you find the TED Talk on the TED website, follow the format for an online video on an organizational website:

Owusu-Kesse, K. (2020, June). 5 needs that any COVID-19 response should meet [Video]. TED Conferences. https://www.ted.com/talks/kwame_owusu_kesse_5_needs_that_any_covid_19_response_should_meet

The speaker is the author in the reference list entry if the video is posted on the TED website. For citations, use the speaker's surname.

TED Talk on YouTube

If you find the TED Talk on YouTube or another streaming video website, follow the usual format for streaming video sites:

TED. (2021, February 5). The shadow pandemic of domestic violence during COVID-19 | Kemi DaSilvalbru [Video]. YouTube. https://www.youtube.com/watch?v=PGdID_ICFII

TED is the author in the reference list entry if the video is posted on YouTube since it is the channel on which the video is posted. For citations, use TED as the author.

Walden University Course Catalog

To include the Walden course catalog in your reference list, use this format:

Walden University. (2020). 2019-2020 Walden University catalog . https://catalog.waldenu.edu/index.php

If you cite from a specific portion of the catalog in your paper, indicate the appropriate section and paragraph number in your text:

...which reflects the commitment to social change expressed in Walden University's mission statement (Walden University, 2020, Vision, Mission, and Goals section, para. 2).

And in the reference list:

Walden University. (2020). Vision, mission, and goals. In 2019-2020 Walden University catalog. https://catalog.waldenu.edu/content.php?catoid=172&navoid=59420&hl=vision&returnto=search

Vartan, S. (2018, January 30). Why vacations matter for your health . CNN. https://www.cnn.com/travel/article/why-vacations-matter/index.html

For webpages on the open web, include the author, date, webpage title, organization/site name, and URL. (There is a slight variation for online versions of print newspapers or magazines. For those sources, follow the models in the previous sections of this page.)

American Federation of Teachers. (n.d.). Community schools . http://www.aft.org/issues/schoolreform/commschools/index.cfm

If there is no specified author, then use the organization’s name as the author. In such a case, there is no need to repeat the organization's name after the title.

In APA 7, active hyperlinks for DOIs and URLs should be used for documents meant for screen reading. Present these hyperlinks in blue and underlined text (the default formatting in Microsoft Word), although plain black text is also acceptable. Be consistent in your formatting choice for DOIs and URLs throughout your reference list.

Related Resources

Knowledge Check: Common Reference List Examples

Didn't find what you need? Email us at [email protected] .

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• Plagiarism and grammar
• Citation guides

APA Citation Generator

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A comprehensive guide to apa citations and format, overview of this guide:.

This page provides you with an overview of APA format, 7th edition. Included is information about referencing, various citation formats with examples for each source type, and other helpful information.

If you’re looking for MLA format , check out the Citation Machine MLA Guide. Also, visit the Citation Machine homepage to use the APA formatter, which is an APA citation generator, and to see more styles .

Being responsible while researching

When you’re writing a research paper or creating a research project, you will probably use another individual’s work to help develop your own assignment. A good researcher or scholar uses another individual’s work in a responsible way. This involves indicating that the work of other individuals is included in your project (i.e., citing), which is one way to prevent plagiarism.

Plagiarism? What is it?

The word plagiarism is derived from the Latin word, plagiare , which means “to kidnap.” The term has evolved over the years to now mean the act of taking another individual’s work and using it as your own, without acknowledging the original author (American Psychological Association, 2020 p. 21). Plagiarism can be illegal and there can be serious ramifications for plagiarizing someone else’s work. Thankfully, plagiarism can be prevented. One way it can be prevented is by including citations and references in your research project. Want to make them quickly and easily? Try the Citation Machine citation generator, which is found on our homepage.

All about citations & references

Citations and references should be included anytime you use another individual’s work in your own assignment. When including a quote, paraphrased information, images, or any other piece of information from another’s work, you need to show where you found it by including a citation and a reference. This guide explains how to make them.

APA style citations are added in the body of a research paper or project and references are added to the last page.

Citations , which are called in-text citations, are included when you’re adding information from another individual’s work into your own project. When you add text word-for-word from another source into your project, or take information from another source and place it in your own words and writing style (known as paraphrasing), you create an in-text citation. These citations are short in length and are placed in the main part of your project, directly after the borrowed information.

References are found at the end of your research project, usually on the last page. Included on this reference list page is the full information for any in-text citations found in the body of the project. These references are listed in alphabetical order by the author's last name.

An APA in-text citation includes only three items: the last name(s) of the author(s), the year the source was published, and sometimes the page or location of the information. References include more information such as the name of the author(s), the year the source was published, the full title of the source, and the URL or page range.

Why is it important to include citations & references

Including APA citations and references in your research projects is a very important component of the research process. When you include citations, you’re being a responsible researcher. You’re showing readers that you were able to find valuable, high-quality information from other sources, place them into your project where appropriate, all while acknowledging the original authors and their work.

Common ways students and scholars accidentally plagiarize

Believe it or not, there are instances when you could attempt to include in-text and full references in the appropriate places, but still accidentally plagiarize. Here are some common mistakes to be aware of:

Mistake #1 - Misquoting sources: If you plan to use a direct quote, make sure you copy it exactly as is. Sure, you can use part of the full quote or sentence, but if you decide to put quotation marks around any words, those words should match exactly what was found in the original source. Here’s a line from The Little Prince , by Antoine de Saint-Exupéry:

“Grown-ups never understand anything by themselves, and it is tiresome for children to be always and forever explaining things to them.”

Here’s an acceptable option:

“Grown-ups never understand anything by themselves,” stated de Saint-Exupéry (1943, p. 3).

Here’s a misquote:

“Grown-ups barely ever understand anything by themselves,” stated de Saint-Exupéry (1943, p. 3).

Notice the slight change in the words. The incorrect phrasing is an instance of accidental plagiarism.

Mistake #2 - Problems with paraphrasing: When we paraphrase, we restate information using our own words and writing style. It’s not acceptable to substitute words from the original source with synonyms.

Let’s use the same sentence from The Little Prince .

A correct paraphrase could be:

de Saint-Exupéry (1943) shares various ways adults frustrate children. One of the biggest being that kids have to explain everything. It’s too bad adults are unable to comprehend anything on their own (p. 3).

An incorrect paraphrase would be:

de Saint-Exupéry (1943) shares that adults never understand anything by themselves, and it is exhausting for kids to be always and forever clarifying things to them (p.3).

Notice how close the incorrect paraphrase is from the original. This is an instance of accidental plagiarism.

Make sure you quote and paraphrase properly in order to prevent accidental plagiarism.

If you’re having a difficult time paraphrasing properly, it is acceptable to paraphrase part of the text AND use a direct quote. Here’s an example:

de Saint-Exupery (1943) shares various ways adults frustrate children. One of the biggest being that kids have to explain everything, and “it is tiresome for children to be always and forever explaining things to them” (p. 3).

Information About APA

Who created it.

The American Psychological Association is an organization created for individuals in the psychology field. With close to 121,000 members, they provide educational opportunities, funding, guidance, and research information for everything psychology-related. They also have numerous high-quality databases, peer-reviewed journals, and books that revolve around mental health.

The American Psychological Association is also credited with creating their own specific citation and reference style. Today, this format is used by individuals not only in the psychology field, but many other subject areas as well. Education, economics, business, and social sciences also use APA style quite frequently. Click here for more information . This guide covers general information about the style, but is not affiliated with the American Psychological Association.

Why was this style created?

This format was first developed in 1929 to form a standardized way for researchers in science fields to document their sources. Prior to the inception of these standards and guidelines, individuals were recognizing the work of other authors by including bits and pieces of information in random order. There wasn’t a set way to format citations and references. You can probably imagine how difficult it was to understand the sources that were used for research projects!

Having a standard format for citing sources allows readers to glance at a citation or APA reference and easily locate the title, author, year published, and other critical pieces of information needed to understand a source.

The evolution of this style

The guide below is based on APA style 7th edition, which was released in 2020. In previous versions of APA format, researchers and scholars were required to include the publisher location for books and the date that an electronic resource was accessed. Both are no longer required to be included.

Details on the differences between the 6th and 7th editions is addressed later in this guide.

Citations & References

The appearance of citations & references.

The format for references varies, but most use this general format:

%%Author’s Last name, First initial. (Date published). Title . URL

Researchers and scholars must look up the proper format for the source that they’re attempting to cite. Books have a certain format, websites have a different format, periodicals have a different format, and so on. Scroll down to find the proper format for the source you’re citing or referencing.

If you would like help citing your sources, CitationMachine.com has a citation generator that will help make the APA citation process much easier for you. To start, simply click on the source type you're citing:

• Journal articles

In-text citations

An APA in-text citation is included in research projects in three instances: When using a direct quote, paraphrasing information, or simply referring to a piece of information from another source.

Quite often, researchers and scholars use a small amount of text, word for word, from another source and include it in their own research projects. This is done for many reasons. Sometimes, another author’s words are so eloquently written that there isn’t a better way to rephrase it yourself. Other times, the author’s words can help prove a point or establish an understanding for something in your research project. When using another author’s exact words in your research project, include an APA in-text citation directly following it.

In addition to using the exact words from another source and placing them into your project, these citations are also added anytime you paraphrase information. Paraphrasing is when you take information from another source and rephrase it, in your own words.

When simply referring to another piece of information from another source, also include a citation directly following it.

Citations in the text are found near a direct quote, paraphrased information, or next to a mention of another source. To see examples of some narrative/ parenthetical citations in action, look at the image above, under “All About Citations & References.”

Note: *Only include the page or paragraph number when using a direct quote or paraphrase. Page numbers have a p. before the number, pp. before the page range, and para. before the paragraph number. This information is included to help the reader locate the exact portion of text themselves. It is unnecessary to include this information when you’re simply referring to another source.

Examples of APA in-text citations:

“Well, you’re about to enter the land of the free and the brave. And I don’t know how you got that stamp on your passport. The priest must know someone” (Tóibín, 2009, p. 52).

Student teachers who use technology in their lessons tend to continue using technology tools throughout their teaching careers (Kent & Giles, 2017, p. 12).

If including the author’s name in the sentence, place the year in the parentheses directly next to his or her name. Add the page number at the end, unless it’s a source without any pages or paragraph numbers (See Section 8.10 of the Publication manual for more details).

In-text citation APA example:

According to a study done by Kent and Giles (2017), student teachers who use technology in their lessons tend to continue using technology tools throughout their teaching careers.

The full references, or citations, for these sources can be found on the last part of a research project, titled the “References.”

Here’s how to create in-text citations for specific amounts of authors:

APA citation with no author

When the source lacks an author’s name, place the title, year, and page number (if available) in the text. The title should be in italics if it sits alone (such as a movie, brochure, or report). If the source is part of a whole (as many web pages and articles are), place the title in quotation marks without italics (See Section 8.14 of the Publication manual ).

Structure of an APA format citation in the text narratively, with the author's name missing:

Title of Source (Year) or “Title of Source” (Year)

Structure of an APA style format citation, in parentheses at the end of the sentence, with the author’s name missing: (Title of Source, Year) or (“Title of Source,” Year)

Structure for one author

In the text, narratively: Last name of Author (Year)...(page number).

In parentheses, at the end of the sentence: (Last name of Author, Year, page number).

Structure for two authors

Place the authors in the order they appear on the source. Only use the ampersand in the parenthetical citations (see Section 8.17 of the Publication manual ). Use ‘and’ to separate the author names if they’re in the text of the sentence.

In the text, narratively: Last name of Author 1 and Last name of Author 2 (Year)....(page number).

In parentheses, at the end of the sentence: (Last name of Author 1 & Last name of Author 2, Year, page number).

Structure for three or more authors

Only include the first listed author’s name in the first and any subsequent citations. Follow it with et al.

(Last name Author 1 et al., Year, page number)

(Agbayani et al., 2020, p. 99)

Last name of Author 1 et al. (Year)...(page).

Agbayani et al. (2020)...(p. 99)

One author, multiple works, same year

What do you do when you want to cite multiple works by an author, and the sources all written in the same year?

Include the letters ‘a’ ‘b’ ‘c’ and so on after the year in the citation.

(Jackson, 2013a)

Jackson (2013a)

Writers can even lump dates together.

Example: Jackson often studied mammals while in Africa (2013a, 2013b).

On the APA reference page, include the same letters in the full references.

Groups and organizations

Write out the full name of the group or organization in the first citation and place the abbreviation next to it in brackets. If the group or organization is cited again, only include the abbreviation. If it doesn’t have an abbreviation associated with it, write out the entire organization’s name each and every time (see Section 8.21 of the Publication manual ).

First APA citation for an organization with an abbreviation: (World Health Organization [WHO], Year)

World Health Organization (WHO, Year)

Notice in the example directly above, the name of the organization is written out in full in the text of the sentence, and the abbreviation is placed in parentheses next to it.

Subsequent APA citations in the text for an organization with an abbreviation: (WHO, Year) OR WHO (Year)

All citations in the text for an organization without an abbreviation: (Citation Machine, Year) or Citation Machine (Year)

One in-text citation, multiple works

Sometimes you’ll need to cite more than one work within an in-text citation. Follow the same format (author, year) format but place semicolons between works (p. 263).

(Obama, 2016; Monroe et al., 1820; Hoover & Coolidge, 1928)

Reminder: There are many citation tools available on CitationMachine.com. Head to our homepage to learn more, check out our APA citation website, and cite your sources easily! The most useful resource on our website? Our APA citation generator, which doesn’t just create full references, it’s also an APA in-text citation website! It’ll do both for you!

Click here to learn more about crediting work .

Reference list citation components

References display the full information for all the citations found in the body of a research project.

Some things to keep in mind when it comes to the references:

• All references sit together on their own page, which is usually the last page(s) of a paper.
• Title the page ‘References’
• Place ‘References’ in the center of the page and bold it. Keep the title in the same font and size as the references. Do not italicize, underline, place the title in quotation marks, or increase the font size.
• The entire page is double spaced.
• All references are listed in alphabetical order by the first word in the reference, which is usually the author’s last name. If the source lacks an author, alphabetize the source by the title (ignore A, An, or The)
• All references have a hanging indent, meaning that the second line of text is indented in half an inch. See examples throughout this guide.
• Remember, each and every citation in the text of the paper MUST have a full reference displayed in the reference list. The citations in the text provide the reader with a quick glimpse about the sources used, but the references in the reference list provide the reader with all the information needed to seek out the source themselves.

Learn more about each component of the reference citation and how to format it in the sections that follow. See an APA sample paper reference list at the end of this entire section.

Author’s names

The names of authors are written in reverse order. Include the initials for the first and middle names. End this information with a period (see Section 9.8 of the Publication manual ).

Format: Last name, F. M.

• Angelou, M.
• Doyle, A. C.

Two or more authors

When two or more authors work together on a source, write them in the order in which they appear on the source. You can name up to 20 authors in the reference. For sources with 2 to 20 authors, place an ampersand (&) before the final author. Use this format:

Last name, F. M., & Last name, F. M.

Last name, F. M., Last name, F. M., Last name, F. M., Last name, F. M., & Last name, F. M.

Kent, A. G., Giles, R. M., Thorpe, A., Lukes, R., Bever, D. J., & He, Y.

If there are 21 or more authors listed on a source, only include the first 19 authors, add three ellipses, and then add the last author’s name.

Roberts, A., Johnson, M. C., Klein, J., Cheng, E. V., Sherman, A., Levin, K. K. , ...Lopez, G. S.

If you plan on using a free APA citation tool, like the one at CitationMachine.com, the names of the authors will format properly for you.

###No authors

If the source lacks an author, place the title in the first position in the reference (Section 9.12 of the Publication manual ). When the source’s title begins with a number (Such as 101 Dalmatians ), place the reference alphabetically as if the number was spelled out. 101 Dalmatians would be placed in the spot where ‘One hundred’ would go, but keep the numbers in their place.

Additionally, if the title begins with the words ‘A’, ‘An,’ or ‘The,’ ignore these words and place the title alphabetically according to the next word.

See the “Titles” section below for more information on formatting the title of sources.

###Corporate/Organization authors

On an APA reference page, corporate authors are always written out in full. In the text of your paper, you may have some abbreviations (such as UN for United Nations), but in the full references, always include the full names of the corporation or organization (following Section 9.11 of the official Publication manual ).

%%United Nations. (2019). Libya: $202 million needed to bring life-saving aid to half a million people hit by humanitarian crisis. https://news.un.org/en/story/2019/02/1031981

Publication date & retrieval date

Directly after the author’s name is the date the source was published. Include the full date for newspapers and magazine articles, and only the year for journals and all other sources. If no date is found on the source, include the initials, n.d. for “no date.”

%% Narducci, M. (2017, May 19). City renames part of 11th Street Ed Snider Way to honor Flyers founder. The Philadelphia Inquirer . http://www.philly.com/

If using our APA Citation Machine, our citation generator will add the correct format for you automatically.

Giving a retrieval date is not needed unless the online content is likely to be frequently updated and changed (e.g., encyclopedia article, dictionary entry, Twitter profile, etc.).

%%Citation Machine [@CiteMachine]. (n.d.). Tweets [Twitter profile]. Twitter. Retrieved October 10, 2019, from https://twitter.com/CiteMachine

When writing out titles for books, articles, chapters, or other non-periodical sources, only capitalize the first word of the title and the first word of the subtitle. Names of people, places, organizations, and other proper nouns also have the first letter capitalized. For books and reports, italicize the title in the APA citation.

Strange case of Dr. Jekyll and Mr. Hyde.

Roots: The saga of an American family.

For articles and chapters in APA referencing, do not italicize the title.

Wake up the nation: Public libraries, policy making, and political discourse.

For newspapers, magazines, journals, newsletters, and other periodicals, capitalize the first letter in each word and italicize the title.

The Seattle Times.

A common question is whether to underline your title or place it in italics or quotation marks in the reference list. Here’s a good general rule: When a source sits alone and is not part of a larger whole, place the title in italics. If the source does not sit alone and is part of a larger whole, do not place it in italics.

Books, movies, journals, and television shows are placed in italics since they stand alone. Songs on an album, episodes of television shows, chapters in books, and articles in journals are not placed in italics since they are smaller pieces of larger wholes.

The Citation Machine citation generator will format the title in your citations automatically.

Additional information about the title

If you feel it would be helpful to include additional information about the source type, include a descriptive noun or two in brackets immediately following the title. Capitalize the first letter.

%%Kennedy, K., & Molen, G. R. (Producers), & Spielberg, S. (Director). (1993). Jurassic Park [Film]. USA: Universal.

Besides [Film], other common notations include:

• [Audio podcast]
• [Letter to the editor]
• [Television series episode]
• [Facebook page]
• [Blog post]
• [Lecture notes]
• [PowerPoint presentation]
• [Video file]

If you are using Citation Machine citing tools, additional information about the title is automatically added for you.

Publisher information

For books and reports, include the publisher name but not the location (see Section 9.29 of the Publication manual ). Older editions of the style required the city, state and/or country, but this hasn't been the case since the 7th edition was released.

It is not necessary to include the entire name of the publisher. It is acceptable to use a brief, intelligible form. However, if Books or Press are part of the publisher’s names, keep these words in the reference. Other common terms, such as Inc., Co., Publishers, and others can be omitted.

For newspapers, journals, magazines, and other periodicals, include the volume and issue number after the title. The volume number is listed first, by itself, in italics. The issue number is in parentheses immediately after it, not italicized. There is no space after the closing parenthesis and before the volume number.

%%Giannoukos, G., Besas, G., Hictour, V., & Georgas, T. (2016). A study on the role of computers in adult education. Educational Research and Reviews , 11 (9), 907-923. https://doi.org/10.5897/ERR2016.2688

After including the publisher information, end this section with a period.

Perseus Books.

Electronic source information:

For online sources, the URL or DOI (Direct Object Identifier) are included at the end of an APA citation.

DOI numbers are often created by publishers for journal articles and other periodical sources. They were created in response to the problem of broken or outdated links and URLs. When a journal article is assigned a DOI number, it is static and will never change. Because of its permanent characteristic, DOIs are the preferred type of electronic information to include in APA citations. When a DOI number is not available, include the source’s URL (see Section 9.34 in the Publication manual ).

For DOIs, include the number in this format:

http://doi.org/xxxx

For URLs, type them in this format:

http:// or https://

Other information about electronic sources:

• If the URL is longer than a line, break it up before a punctuation mark.
• Do not place a period at the end of the citation/URL.
• It is unnecessary to include retrieval dates, unless the source changes often over time (like in a Wikipedia article).
• It is not necessary to include the names of databases

If using the Citation Machine APA citation website autocite features, the online publication information will be automatically replaced by the DOI. The Citation Machine APA template will properly cite your online sources for you.

Make sure you run your completed paper through the Citation Machine Plus smart proofreader, which scans for grammar, spelling, and plagiarism. Whether it’s an adjective , verb , or pronoun out-of-place, our technology helps edits your paper for you!

Annotated bibliographies:

An APA annotated bibliography is a full bibliography that includes a small note for each reference citation. Each note should be short (1-2 paragraphs) and contain a summary or your evaluation about each source. When creating your citations on CitationMachine.net, there is a field at the bottom of each form to add your own annotations.

Follow the publication manual guidelines on paper format and writing style. Let your instructor guide other details about your annotations. Still confused? Read our guide on annotated bibliographies .

These types of projects look different depending on the style you’re using. Use the link at the top of the page to access resources related to the Modern Language Association’s style. Here’s information related to Chicago citation style .

Page formatting

Need help with the design and formatting of your paper? Look no further! This section provides the ins and outs of properly displaying the information in your APA essay.

• Times New Roman, 12-point size.
• Calibri, Arial, or Georgia, 11-point size
• Lucida, Sans Unicode, or Computer Modern, 10-point size
• Indents = Every paragraph should start with an indent.
• Margins = 1 inch around the entire document
• Spacing = Double space everything!

Arrange your pages in this order:

• Page 1 - APA Title Page (see below for information on the title page)
• Page 2 - Abstract (If your professor requests one)
• Page 3 - First page of text
• References begin on their own page. Include the list of references on the page after the text.
• Tables and figures

Keep in mind that the order above is the recommendation for papers being submitted for peer review. If you’re writing an APA style paper for a class, your professor may be more lenient about the requirements. Also, if you’re submitting your paper for a specific journal, check the requirements on the journal’s website. Each journal has different rules and procedures.

Just a little nudge to remind you about the Citation Machine Plus smart proofreader. Whether it’s a conjunction or interjection out of place, a misspelled word, or an out of place citation, we’ll offer suggestions for improvement! Don’t forget to check out our APA citation maker while you’re at it!

Running heads

In older editions of APA, running heads were required for all papers. Since the 7th edition, that’s changed.

• Student paper: No running head
• Professional paper: Include a running head

The running head displays the title of the paper and the page number on all pages of the paper. This header is found on every page of a professional paper (not a student paper), even on the title page (sometimes called an APA cover page) and reference list (taken from Section 2.8 of the Publication manual ).

It's displayed all in capital letters at the top of the page. Across from the running head, along the right margin, is the page number.

• Use the header feature in your word processor. Both Google Docs and Word have these features available.
• Use one for the recommended fonts mentioned under "Page formatting."

Title pages

A title page, sometimes called an APA cover page, graces the cover of an essay or paper. An APA title page should follow rules from Section 2.3 of the official Publication manual and include:

• Page number, which is page 1
• Use title case and bold font
• The title should be under 12 words in length
• The title should be a direct explanation of the focus of the paper. Do not include any unnecessary descriptors such as “An Analysis of…” or “A Study of…”
• Exclude any labels such as Mr., Ms., Dr, PhD...
• Name of the school or institution
• Course number and/or class name
• Name of your instructor, including their preferred honorifics (e.g., PhD, Dr., etc.)
• Paper’s due date
• If this is a professional paper, also include a running head. If this is a student paper, do not include one.

Follow the directions for the running head and page number in the section above. Below the running head, a few lines beneath, and centered in the middle of the page, should be the title. The next line below is the author’s name(s), followed by the name of the school or institution, the class or course name, your instructor’s name, and the paper’s due date.

All components on this page should be written in the same font and size as the rest of your paper. Double space the title, names, name of school or institution, and all other information on the page (except for the running head and page number).

Example - Student Title Page APA:

Example - Professional Title Page APA:

If you’re submitting your paper to a journal for publication, check the journal’s website for exact requirements. Each journal is different and some may request a different type of APA format cover page.

Looking to create an APA format title page? Head to CitationMachine.com’s homepage and choose “Title Page” at the top of the screen.

An abstract briefly but thoroughly summarizes dissertation contents. It’s found in the beginning of a professional paper, right after the title page. Abstracts are meant to help readers determine whether to continue reading the entire document. With that in mind, try to craft the lead sentence to entice the reader to continue reading.

Here are a few tips:

• Be factual and keep your opinions out. An abstract should accurately reflect the paper or dissertation and should not involve information or commentary not in the thesis.
• Communicate your main thesis. What was the examined problem or hypothesis? A reader should know this from reading your abstract.
• Keep it brief. Stick to the main points and don’t add unnecessary words or facts. It should not exceed 250 words.
• Consider your paper’s purpose. It’s important to cater your abstract to your paper type and think about what information the target audience for that paper type would want. For example, an empirical article may mention methodology or participant description. A quantitative or qualitative meta-analysis would mention the different variables considered and how information was synthesized.
• Use verbs over noun equivalents, and active voice. Example: “There was research into…” becomes “We researched…”

Formatting guidelines:

• The abstract goes after the title page.
• It should have the same font (size and type) as the rest of the paper.
• It should stick to one page.
• Double-space all page text.
• Center and bold the word “Abstract” at the top of the paper.
• Don’t indent the first line of the abstract body. The body should also be in plain text.
• For the keywords, place it on the line after the abstract and indent the first line (but not subsequent lines). The word “Keywords:” is capitalized, italicized, and followed by a colon. The actual keywords are sentence case and in plan font.
• List each keyword one after the other, and separate them by a comma.
• After the last keyword, no ending punctuation is needed.

Tables & Figures

If your paper includes a lot of numerical information or data, you may want to consider placing it into a table or a figure, rather than typing it all out. A visual figure or simple, organized table filled with numerical data is often easier for readers to digest and comprehend than tons of paragraphs filled with numbers. Chapter 7 of the Publication manual outlines formatting for tables and figures. Let's cover the basics below.

If you’d like to include a table or figure in your paper, here are a few key pieces of information to keep in mind:

• At the end of the paper after the APA reference page
• In the text after it is first mentioned
• The table first mentioned in the text should be titled ‘Table 1.’ The next table mentioned in the text is ‘Table 2,’ and so on. For figures, it would be 'Figure 1,' 'Figure 2,' and so forth.

• Even though every table and figure is numbered, also create a title for each that describes the information it contains. Capitalize all important words in the title.
• For tables, do not use any vertical lines, only use horizontal to break up information and headings.
• Single spacing is acceptable to use in tables and figures. If you prefer double spacing your information, that is okay too.
• Do not include extra information or “fluff.” Keep it simple!
• Do not include the same exact information in the paper. Only include the complete information in one area—the table or the text.
• All tables and figures must be referenced in the text. It is unacceptable to throw a table or figure into the back of the paper without first providing a brief summary or explanation of its relevance.

Publication Manual 6th Edition vs 7th Edition

The 6th edition of the Publication Manual of the American Psychological Association was released in 2009. The current 7th edition came out in the fall of 2019 and was designed to be more student focused, provide more guidance on accessibility, and address changes that have developed over the last 10 years.

Below, we’ve listed what we feel are the most relevant changes related to APA format.

Journals and DOIs

DOI stands for “digital object identifier.” Many journal articles use and have a unique DOI that should be included in a full citation.

When including a DOI in a citation, format it as a URL. Do not label it “DOI.” Articles without DOIs from databases are treated as print works. For example:

6th edition:

%%Gänsicke, B. T., Schreiber, M. R., Toloza, O., Fusillo, N. P. G., Koester, D., & Manser, C. J. (2019). Accretion of a giant planet onto a white dwarf star. Nature, 576 (7785), 61–64. doi: 10.1038/s41586-019-1789-8

7th edition:

%%Gänsicke, B. T., Schreiber, M. R., Toloza, O., Fusillo, N. P. G., Koester, D., & Manser, C. J. (2019). Accretion of a giant planet onto a white dwarf star. Nature, 576 (7785), 61–64. https://doi.org/10.1038/s41586-019-1789-8

Citing Books

There are few new guidelines when you are citing a book. First, the publisher location no longer needs to be indicated.

%%Zack, P. O. (2001). The shoals of time. Bloomington, IN: First Books Library.

%%Zack, P. O. (2001). The shoals of time. First Books Library.

Second, the format of an ebook (e.g., Kindle, etc.) no longer needs to be indicated.

%%Niven, J. (2012). Ada Blackjack: A true story of survival in the Arctic [Kindle].

%%Niven, J. (2012). Ada Blackjack: A true story of survival in the Arctic .

Lastly, books from research databases without DOIs are treated the same as print works.

When using a URL in a citation, you no longer need to include the term “Retrieved from” before URLs (except with retrieval dates). The font should be blue and underlined, or black and not underlined.

6th Edition:

%%Flood, A. (2019, December 6). Britain has closed almost 800 libraries since 2010, figures show. The Guardian . Retrieved from https://www.theguardian.com/books/2019/dec/06/britain-has-closed-almost-800-libraries-since-2010-figures-show

7th Edition:

%%Flood, A. (2019, December 6). Britain has closed almost 800 libraries since 2010, figures show. The Guardian . https://www.theguardian.com/books/2019/dec/06/britain-has-closed-almost-800-libraries-since-2010-figures-show

Within a full APA citation, you may spell out up to 20 author names. For two to 20 authors, include an ampersand (&) before the name of the last author. For sources with 21 or more authors, structure it as follows:

Structure: First 19 authors’ names, . . . Last author’s name.

7th edition example: Washington, G., Adams, J., Jefferson, T., Madison, J., Monroe, J., Adams, J. Q., Jackson, A., Van Buren, M., Harrison, W. H., Tyler, J., Polk, J. K., Taylor, Z., Filmore, M., Pierce, F., Buchanan, J., Lincoln, A., Johnson, A., Grant, U. S., Hayes, R. B., Garfield, . . . Trump, D.

When creating an in-text citation for a source with 3 or more authors, use “et al.” after the first author’s name. This helps abbreviate the mention.

6th Edition: (Honda, Johnson, Prosser, Rossi, 2019)

7th Edition: (Honda et al., 2019)

Tables and Figures

Instead of having different formats for tables and figures, both use one standardized format. Now both tables and figures have a number, a title, name of the table/figure, and a note at the bottom.

If you’re still typing into Google “how to cite a website APA” among other related questions and keywords, click here for further reading on the style .

When you’re through with your writing, toss your entire paper into the Citation Machine Plus plagiarism checker , which will scan your paper for grammar edits and give you up to 5 suggestions cards for free! Worry less about a determiner , preposition , or adverb out of place and focus on your research!

American Psychological Association. (2020). Publication manual of the American Psychological Association (7th ed.) (2020). American Psychological Association. https://doi.org/10.1037/0000165-000

Updated March 3, 2020

Written and edited by Michele Kirschenbaum and Wendy Ikemoto. Michele Kirschenbaum has been an awesome school librarian since 2006 and is an expert in citing sources. Wendy Ikemoto has a master’s degree in library and information science and has been working for Citation Machine since 2012.

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16.1: Formatting a Research Paper

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Learning Objectives

• Identify the major components of a research paper written using American Psychological Association (APA) style.
• Apply general APA style and formatting conventions in a research paper.

In this chapter, you will learn how to use APA style, the documentation and formatting style followed by the American Psychological Association, as well as MLA style, from the Modern Language Association. There are a few major formatting styles used in academic texts, including AMA, Chicago, and Turabian:

• AMA (American Medical Association) for medicine, health, and biological sciences
• APA (American Psychological Association) for education, psychology, and the social sciences
• Chicago—a common style used in everyday publications like magazines, newspapers, and books
• MLA (Modern Language Association) for English, literature, arts, and humanities
• Turabian—another common style designed for its universal application across all subjects and disciplines

While all the formatting and citation styles have their own use and applications, in this chapter we focus our attention on the two styles you are most likely to use in your academic studies: APA and MLA.

If you find that the rules of proper source documentation are difficult to keep straight, you are not alone. Writing a good research paper is, in and of itself, a major intellectual challenge. Having to follow detailed citation and formatting guidelines as well may seem like just one more task to add to an already-too-long list of requirements.

Following these guidelines, however, serves several important purposes. First, it signals to your readers that your paper should be taken seriously as a student’s contribution to a given academic or professional field; it is the literary equivalent of wearing a tailored suit to a job interview. Second, it shows that you respect other people’s work enough to give them proper credit for it. Finally, it helps your reader find additional materials if he or she wishes to learn more about your topic.

Furthermore, producing a letter-perfect APA-style paper need not be burdensome. Yes, it requires careful attention to detail. However, you can simplify the process if you keep these broad guidelines in mind:

• Work ahead whenever you can. Chapter 11 includes tips for keeping track of your sources early in the research process, which will save time later on.
• Get it right the first time. Apply APA guidelines as you write, so you will not have much to correct during the editing stage. Again, putting in a little extra time early on can save time later.
• Use the resources available to you. In addition to the guidelines provided in this chapter, you may wish to consult the APA website at http://www.apa.org or the Purdue University Online Writing lab at http://owl.english.purdue.edu , which regularly updates its online style guidelines.

General Formatting Guidelines

This chapter provides detailed guidelines for using the citation and formatting conventions developed by the American Psychological Association, or APA. Writers in disciplines as diverse as astrophysics, biology, psychology, and education follow APA style. The major components of a paper written in APA style are listed in the following box.

These are the major components of an APA-style paper:

• Headings and, if necessary, subheadings to organize the content
• In-text citations of research sources
• References page

All these components must be saved in one document, not as separate documents.

The title page of your paper includes the following information:

• Title of the paper
• Author’s name
• Name of the institution with which the author is affiliated
• Header at the top of the page with the paper title (in capital letters) and the page number (If the title is lengthy, you may use a shortened form of it in the header.)

List the first three elements in the order given in the previous list, centered about one third of the way down from the top of the page. Use the headers and footers tool of your word-processing program to add the header, with the title text at the left and the page number in the upper-right corner. Your title page should look like the following example.

The next page of your paper provides an abstract, or brief summary of your findings. An abstract does not need to be provided in every paper, but an abstract should be used in papers that include a hypothesis. A good abstract is concise—about one hundred to one hundred fifty words—and is written in an objective, impersonal style. Your writing voice will not be as apparent here as in the body of your paper. When writing the abstract, take a just-the-facts approach, and summarize your research question and your findings in a few sentences.

In Chapter 12, you read a paper written by a student named Jorge, who researched the effectiveness of low-carbohydrate diets. Read Jorge’s abstract. Note how it sums up the major ideas in his paper without going into excessive detail.

Exercise \(\PageIndex{1}\)

Write an abstract summarizing your paper. Briefly introduce the topic, state your findings, and sum up what conclusions you can draw from your research. Use the word count feature of your word-processing program to make sure your abstract does not exceed one hundred fifty words.

Depending on your field of study, you may sometimes write research papers that present extensive primary research, such as your own experiment or survey. In your abstract, summarize your research question and your findings, and briefly indicate how your study relates to prior research in the field.

Margins, Pagination, and Headings

APA style requirements also address specific formatting concerns, such as margins, pagination, and heading styles, within the body of the paper. Review the following APA guidelines.

Use these general guidelines to format the paper:

• Set the top, bottom, and side margins of your paper at 1 inch.
• Use double-spaced text throughout your paper.
• Use a standard font, such as Times New Roman or Arial, in a legible size (10- to 12-point).
• Use continuous pagination throughout the paper, including the title page and the references section. Page numbers appear flush right within your header.
• Section headings and subsection headings within the body of your paper use different types of formatting depending on the level of information you are presenting. Additional details from Jorge’s paper are provided.

Exercise \(\PageIndex{2}\)

Begin formatting the final draft of your paper according to APA guidelines. You may work with an existing document or set up a new document if you choose. Include the following:

• Your title page
• The abstract you created in Exercise 1
• Correct headers and page numbers for your title page and abstract

APA style uses section headings to organize information, making it easy for the reader to follow the writer’s train of thought and to know immediately what major topics are covered. Depending on the length and complexity of the paper, its major sections may also be divided into subsections, sub-subsections, and so on. These smaller sections, in turn, use different heading styles to indicate different levels of information. In essence, you are using headings to create a hierarchy of information.

The following heading styles used in APA formatting are listed in order of greatest to least importance:

• Section headings use centered, boldface type. Headings use title case, with important words in the heading capitalized.
• Subsection headings use left-aligned, boldface type. Headings use title case.
• The third level uses left-aligned, indented, boldface type. Headings use a capital letter only for the first word, and they end in a period.
• The fourth level follows the same style used for the previous level, but the headings are boldfaced and italicized.
• The fifth level follows the same style used for the previous level, but the headings are italicized and not boldfaced.

Visually, the hierarchy of information is organized as indicated in Table 13.1 “Section Headings”.

A college research paper may not use all the heading levels shown in Table 13.1 “Section Headings”, but you are likely to encounter them in academic journal articles that use APA style. For a brief paper, you may find that level 1 headings suffice. Longer or more complex papers may need level 2 headings or other lower-level headings to organize information clearly. Use your outline to craft your major section headings and determine whether any subtopics are substantial enough to require additional levels of headings.

Exercise \(\PageIndex{3}\)

Working with the document you developed in Note 13.11 “Exercise 2”, begin setting up the heading structure of the final draft of your research paper according to APA guidelines. Include your title and at least two to three major section headings, and follow the formatting guidelines provided above. If your major sections should be broken into subsections, add those headings as well. Use your outline to help you.

Because Jorge used only level 1 headings, his Exercise 3 would look like the following:

Citation Guidelines

In-text citations.

Throughout the body of your paper, include a citation whenever you quote or paraphrase material from your research sources. As you learned in Chapter 11, the purpose of citations is twofold: to give credit to others for their ideas and to allow your reader to follow up and learn more about the topic if desired. Your in-text citations provide basic information about your source; each source you cite will have a longer entry in the references section that provides more detailed information.

In-text citations must provide the name of the author or authors and the year the source was published. (When a given source does not list an individual author, you may provide the source title or the name of the organization that published the material instead.) When directly quoting a source, it is also required that you include the page number where the quote appears in your citation.

This information may be included within the sentence or in a parenthetical reference at the end of the sentence, as in these examples.

Epstein (2010) points out that “junk food cannot be considered addictive in the same way that we think of psychoactive drugs as addictive” (p. 137).

Here, the writer names the source author when introducing the quote and provides the publication date in parentheses after the author’s name. The page number appears in parentheses after the closing quotation marks and before the period that ends the sentence.

Addiction researchers caution that “junk food cannot be considered addictive in the same way that we think of psychoactive drugs as addictive” (Epstein, 2010, p. 137).

Here, the writer provides a parenthetical citation at the end of the sentence that includes the author’s name, the year of publication, and the page number separated by commas. Again, the parenthetical citation is placed after the closing quotation marks and before the period at the end of the sentence.

As noted in the book Junk Food, Junk Science (Epstein, 2010, p. 137), “junk food cannot be considered addictive in the same way that we think of psychoactive drugs as addictive.”

Here, the writer chose to mention the source title in the sentence (an optional piece of information to include) and followed the title with a parenthetical citation. Note that the parenthetical citation is placed before the comma that signals the end of the introductory phrase.

David Epstein’s book Junk Food, Junk Science (2010) pointed out that “junk food cannot be considered addictive in the same way that we think of psychoactive drugs as addictive” (p. 137).

Another variation is to introduce the author and the source title in your sentence and include the publication date and page number in parentheses within the sentence or at the end of the sentence. As long as you have included the essential information, you can choose the option that works best for that particular sentence and source.

Citing a book with a single author is usually a straightforward task. Of course, your research may require that you cite many other types of sources, such as books or articles with more than one author or sources with no individual author listed. You may also need to cite sources available in both print and online and nonprint sources, such as websites and personal interviews. Section 13.2 and Section 13.3 provide extensive guidelines for citing a variety of source types.

writing at work

APA is just one of several different styles with its own guidelines for documentation, formatting, and language usage. Depending on your field of interest, you may be exposed to additional styles, such as the following:

• MLA style. Determined by the Modern Languages Association and used for papers in literature, languages, and other disciplines in the humanities.
• Chicago style. Outlined in the Chicago Manual of Style and sometimes used for papers in the humanities and the sciences; many professional organizations use this style for publications as well.
• Associated Press (AP) style. Used by professional journalists.

References List

The brief citations included in the body of your paper correspond to the more detailed citations provided at the end of the paper in the references section. In-text citations provide basic information—the author’s name, the publication date, and the page number if necessary—while the references section provides more extensive bibliographical information. Again, this information allows your reader to follow up on the sources you cited and do additional reading about the topic if desired.

The specific format of entries in the list of references varies slightly for different source types, but the entries generally include the following information:

• The name(s) of the author(s) or institution that wrote the source
• The year of publication and, where applicable, the exact date of publication
• The full title of the source
• For books, the city of publication
• For articles or essays, the name of the periodical or book in which the article or essay appears
• For magazine and journal articles, the volume number, issue number, and pages where the article appears
• For sources on the web, the URL where the source is located

The references page is double spaced and lists entries in alphabetical order by the author’s last name. If an entry continues for more than one line, the second line and each subsequent line are indented five spaces. Review the following example. (Section 13.3 provides extensive guidelines for formatting reference entries for different types of sources.)

In APA style, book and article titles are formatted in sentence case, not title case. Sentence case means that only the first word is capitalized, along with any proper nouns.

Key Takeaways

• Following proper citation and formatting guidelines helps writers ensure that their work will be taken seriously, give proper credit to other authors for their work, and provide valuable information to readers.
• Working ahead and taking care to cite sources correctly the first time are ways writers can save time during the editing stage of writing a research paper.
• APA papers usually include an abstract that concisely summarizes the paper.
• APA papers use a specific headings structure to provide a clear hierarchy of information.
• In APA papers, in-text citations usually include the name(s) of the author(s) and the year of publication.
• In-text citations correspond to entries in the references section, which provide detailed bibliographical information about a source.

Child Behavioral Health

• Background Information
• Data/Statistics
• Citing in APA Style

UO Portland Library Help

College of Education Librarian

This page is intended as a general introduction to citing sources using the bibliographic style established by the American Psychological Association (APA). For more complete details, see the most recent edition of the Publication Manual of the American Psychological Association (REF KNIGHT BF76.7 .P83 2020). Note that the manual includes essential information on manuscript preparation (e.g., margins, use of the passive voice), creating figures and tables, and ethics.

In October 2019, the American Psychological Association published its 7th edition of the APA Publication Manual, which replaced the 6th edition from 2009. To learn about the major changes in the APA guidelines, please consult this  video tutorial . 

Additional Resources:

Online Resources

• APA Style - Excelsior OWL
• APA Reference Examples (Official)

Sample References

Sample list of references.

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🤔 What is a Harvard Referencing Generator?

A Harvard Referencing Generator is a tool that automatically generates formatted academic references in the Harvard style.

It takes in relevant details about a source -- usually critical information like author names, article titles, publish dates, and URLs -- and adds the correct punctuation and formatting required by the Harvard referencing style.

The generated references can be copied into a reference list or bibliography, and then collectively appended to the end of an academic assignment. This is the standard way to give credit to sources used in the main body of an assignment.

👩‍🎓 Who uses a Harvard Referencing Generator?

Harvard is the main referencing style at colleges and universities in the United Kingdom and Australia. It is also very popular in other English-speaking countries such as South Africa, Hong Kong, and New Zealand. University-level students in these countries are most likely to use a Harvard generator to aid them with their undergraduate assignments (and often post-graduate too).

🙌 Why should I use a Harvard Referencing Generator?

A Harvard Referencing Generator solves two problems:

• It provides a way to organise and keep track of the sources referenced in the content of an academic paper.
• It ensures that references are formatted correctly -- inline with the Harvard referencing style -- and it does so considerably faster than writing them out manually.

A well-formatted and broad bibliography can account for up to 20% of the total grade for an undergraduate-level project, and using a generator tool can contribute significantly towards earning them.

⚙️ How do I use MyBib's Harvard Referencing Generator?

Here's how to use our reference generator:

• If citing a book, website, journal, or video: enter the URL or title into the search bar at the top of the page and press the search button.
• Choose the most relevant results from the list of search results.
• Our generator will automatically locate the source details and format them in the correct Harvard format. You can make further changes if required.
• Then either copy the formatted reference directly into your reference list by clicking the 'copy' button, or save it to your MyBib account for later.

MyBib supports the following for Harvard style:

🍏 What other versions of Harvard referencing exist?

There isn't "one true way" to do Harvard referencing, and many universities have their own slightly different guidelines for the style. Our generator can adapt to handle the following list of different Harvard styles:

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Daniel is a qualified librarian, former teacher, and citation expert. He has been contributing to MyBib since 2018.

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Reference List: Basic Rules

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This resourse, revised according to the 7 th  edition APA Publication Manual, offers basic guidelines for formatting the reference list at the end of a standard APA research paper. Most sources follow fairly straightforward rules. However, because sources obtained from academic journals  carry special weight in research writing, these sources are subject to special rules . Thus, this page presents basic guidelines for citing academic journals separate from its "ordinary" basic guidelines. This distinction is made clear below.

Note:  Because the information on this page pertains to virtually all citations, we've highlighted one important difference between APA 6 and APA 7 with an underlined note written in red.  For more information, please consult the   Publication Manual of the American Psychological Association , (7 th  ed.).

Formatting a Reference List

Your reference list should appear at the end of your paper. It provides the information necessary for a reader to locate and retrieve any source you cite in the body of the paper. Each source you cite in the paper must appear in your reference list; likewise, each entry in the reference list must be cited in your text.

Your references should begin on a new page separate from the text of the essay; label this page "References" in bold, centered at the top of the page (do NOT underline or use quotation marks for the title). All text should be double-spaced just like the rest of your essay.

Basic Rules for Most Sources

• All lines after the first line of each entry in your reference list should be indented one-half inch from the left margin. This is called hanging indentation.
• All authors' names should be inverted (i.e., last names should be provided first).
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• Published: 08 May 2024

Accurate structure prediction of biomolecular interactions with AlphaFold 3

• Josh Abramson   ORCID: orcid.org/0009-0000-3496-6952 1   na1 ,
• Jonas Adler   ORCID: orcid.org/0000-0001-9928-3407 1   na1 ,
• Jack Dunger 1   na1 ,
• Richard Evans   ORCID: orcid.org/0000-0003-4675-8469 1   na1 ,
• Tim Green   ORCID: orcid.org/0000-0002-3227-1505 1   na1 ,
• Alexander Pritzel   ORCID: orcid.org/0000-0002-4233-9040 1   na1 ,
• Olaf Ronneberger   ORCID: orcid.org/0000-0002-4266-1515 1   na1 ,
• Lindsay Willmore   ORCID: orcid.org/0000-0003-4314-0778 1   na1 ,
• Andrew J. Ballard   ORCID: orcid.org/0000-0003-4956-5304 1 ,
• Joshua Bambrick   ORCID: orcid.org/0009-0003-3908-0722 2 ,
• Sebastian W. Bodenstein 1 ,
• David A. Evans 1 ,
• Chia-Chun Hung   ORCID: orcid.org/0000-0002-5264-9165 2 ,
• Michael O’Neill 1 ,
• David Reiman   ORCID: orcid.org/0000-0002-1605-7197 1 ,
• Kathryn Tunyasuvunakool   ORCID: orcid.org/0000-0002-8594-1074 1 ,
• Zachary Wu   ORCID: orcid.org/0000-0003-2429-9812 1 ,
• Akvilė Žemgulytė 1 ,
• Eirini Arvaniti 3 ,
• Charles Beattie   ORCID: orcid.org/0000-0003-1840-054X 3 ,
• Ottavia Bertolli   ORCID: orcid.org/0000-0001-8578-3216 3 ,
• Alex Bridgland 3 ,
• Alexey Cherepanov   ORCID: orcid.org/0000-0002-5227-0622 4 ,
• Miles Congreve 4 ,
• Alexander I. Cowen-Rivers 3 ,
• Andrew Cowie   ORCID: orcid.org/0000-0002-4491-1434 3 ,
• Michael Figurnov   ORCID: orcid.org/0000-0003-1386-8741 3 ,
• Fabian B. Fuchs 3 ,
• Hannah Gladman 3 ,
• Rishub Jain 3 ,
• Yousuf A. Khan   ORCID: orcid.org/0000-0003-0201-2796 3 ,
• Caroline M. R. Low 4 ,
• Kuba Perlin 3 ,
• Anna Potapenko 3 ,
• Pascal Savy 4 ,
• Sukhdeep Singh 3 ,
• Adrian Stecula   ORCID: orcid.org/0000-0001-6914-6743 4 ,
• Ashok Thillaisundaram 3 ,
• Catherine Tong   ORCID: orcid.org/0000-0001-7570-4801 4 ,
• Sergei Yakneen   ORCID: orcid.org/0000-0001-7827-9839 4 ,
• Ellen D. Zhong   ORCID: orcid.org/0000-0001-6345-1907 3 ,
• Michal Zielinski 3 ,
• Augustin Žídek   ORCID: orcid.org/0000-0002-0748-9684 3 ,
• Victor Bapst 1   na2 ,
• Pushmeet Kohli   ORCID: orcid.org/0000-0002-7466-7997 1   na2 ,
• Max Jaderberg   ORCID: orcid.org/0000-0002-9033-2695 2   na2 ,
• Demis Hassabis   ORCID: orcid.org/0000-0003-2812-9917 1 , 2   na2 &
• John M. Jumper   ORCID: orcid.org/0000-0001-6169-6580 1   na2  

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• Drug discovery
• Machine learning
• Protein structure predictions
• Structural biology

The introduction of AlphaFold 2 1 has spurred a revolution in modelling the structure of proteins and their interactions, enabling a huge range of applications in protein modelling and design 2–6 . In this paper, we describe our AlphaFold 3 model with a substantially updated diffusion-based architecture, which is capable of joint structure prediction of complexes including proteins, nucleic acids, small molecules, ions, and modified residues. The new AlphaFold model demonstrates significantly improved accuracy over many previous specialised tools: far greater accuracy on protein-ligand interactions than state of the art docking tools, much higher accuracy on protein-nucleic acid interactions than nucleic-acid-specific predictors, and significantly higher antibody-antigen prediction accuracy than AlphaFold-Multimer v2.3 7,8 . Together these results show that high accuracy modelling across biomolecular space is possible within a single unified deep learning framework.

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Highly accurate protein structure prediction with AlphaFold

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These authors contributed equally: Josh Abramson, Jonas Adler, Jack Dunger, Richard Evans, Tim Green, Alexander Pritzel, Olaf Ronneberger, Lindsay Willmore

These authors jointly supervised this work: Victor Bapst, Pushmeet Kohli, Max Jaderberg, Demis Hassabis, John M. Jumper

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Core Contributor, Google DeepMind, London, UK

Josh Abramson, Jonas Adler, Jack Dunger, Richard Evans, Tim Green, Alexander Pritzel, Olaf Ronneberger, Lindsay Willmore, Andrew J. Ballard, Sebastian W. Bodenstein, David A. Evans, Michael O’Neill, David Reiman, Kathryn Tunyasuvunakool, Zachary Wu, Akvilė Žemgulytė, Victor Bapst, Pushmeet Kohli, Demis Hassabis & John M. Jumper

Core Contributor, Isomorphic Labs, London, UK

Joshua Bambrick, Chia-Chun Hung, Max Jaderberg & Demis Hassabis

Google DeepMind, London, UK

Eirini Arvaniti, Charles Beattie, Ottavia Bertolli, Alex Bridgland, Alexander I. Cowen-Rivers, Andrew Cowie, Michael Figurnov, Fabian B. Fuchs, Hannah Gladman, Rishub Jain, Yousuf A. Khan, Kuba Perlin, Anna Potapenko, Sukhdeep Singh, Ashok Thillaisundaram, Ellen D. Zhong, Michal Zielinski & Augustin Žídek

Isomorphic Labs, London, UK

Alexey Cherepanov, Miles Congreve, Caroline M. R. Low, Pascal Savy, Adrian Stecula, Catherine Tong & Sergei Yakneen

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Correspondence to Max Jaderberg , Demis Hassabis or John M. Jumper .

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This Supplementary Information file contains the following 9 sections: (1) Notation; (2) Data pipeline; (3) Model architecture; (4) Auxiliary heads; (5) Training and inference; (6) Evaluation; (7) Differences to AlphaFold2 and AlphaFold-Multimer; (8) Supplemental Results; and (9) Appendix: CCD Code and PDB ID tables.

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Abramson, J., Adler, J., Dunger, J. et al. Accurate structure prediction of biomolecular interactions with AlphaFold 3. Nature (2024). https://doi.org/10.1038/s41586-024-07487-w

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ORIGINAL RESEARCH article

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Building the Future of Education Together: Innovation, Complexity, Sustainability, Interdisciplinary Research and Open Science

Developing the Skills for Complex Thinking Research: A Case Study Using Social Robotics to Produce Scientific Papers Provisionally Accepted

• 1 Institute for the Future of Education, Monterrey Institute of Technology and Higher Education (ITESM), Mexico
• 2 University of Cienfuegos, Cuba

The final, formatted version of the article will be published soon.

The development of university students' skills to successfully produce scientific documents has been a recurring topic of study in academia. This paper analyzes the implementation of a training experience using a digital environment mediated by video content materials starring humanoid robots. The research aimed to scale complex thinking and its subcompetencies as a hinge to strengthen basic academic research skills. Students from Colombia, Ecuador, and Mexico committed to preparing a scientific document as part of their professional training participated. A pretest to know their initial level of perception, a posttest to evaluate if there was a change, and a scientific document the students delivered at the end of the training experience comprised the methodology to demonstrate the improvement of their skills. The results indicated students' perceived improvement in the sub-competencies of systemic, creative, scientific, and innovative thinking; however, their perceptions did not align with that of the tutor who reviewed the delivered scientific product. The conclusion was that although the training experience helped strengthen the students' skills, variables that are determinants for a student to develop the knowledge necessary to prepare scientific documents and their derived products remain to be analyzed.

Keywords: higher education, research skills, Educational innovation, complex thinking, scientific thinking, Critical Thinking, Innovative thinking, social robotics

Received: 16 Oct 2023; Accepted: 17 May 2024.

Copyright: © 2024 Lopez-Caudana, George-Reyes and Avello-Martínez. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) . The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

* Correspondence: Dr. Edgar O. Lopez-Caudana, Institute for the Future of Education, Monterrey Institute of Technology and Higher Education (ITESM), Monterrey, Mexico

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Models were stratified by age, cohort (sex), and calendar time, and adjusted for Southern European/Mediterranean ancestry (yes/no), married (yes/no), living alone (yes/no), smoking status (never, former, current smoker 1-14 cigarettes/d, 15-24 cigarettes/d, or ≥25 cigarettes/d), physical activity (<3.0, 3.0-8.9, 9.0-17.9, 18.0-26.9, ≥27.0 metabolic equivalent of task–h/wk), multivitamin use (yes/no), history of hypertension (yes/no), history of hypercholesterolemia (yes/no), history of diabetes (yes/no), in women postmenopausal status and menopausal hormone use (premenopausal, postmenopausal [no, past, or current hormone use]), total energy intake (kcal/d), family history of dementia (yes/no), history of depression (yes/no), census socioeconomic status (9-variable score, in quintiles), and body mass index calculated as weight in kilograms divided by height in meters squared (<23, 23-25, 25-30, 30-35, ≥35). Pooled results were obtained by pooling the datasets of the cohorts. AMED score is without monounsaturated:saturated fats intake ratio component. AHEI score is without polyunsaturated fats intake component. HR indicates hazard ratio.

a Reference value.

b P  < .05.

Substitution analysis of 5 g/d intake of olive oil for the equivalent amount of butter, other vegetable oils, mayonnaise, and margarine. All Cox proportional hazards models were stratified by age and calendar time. Models were adjusted for Southern European/Mediterranean ancestry (yes/no), married (yes/no), living alone (yes/no), smoking status (never, former, current smoker 1-14 cigarettes/d, 15-24 cigarettes/d, or ≥25 cigarettes/d), alcohol intake (0, 0.1-4.9, 5.0-9.9, 10.0-14.9, and ≥15.0 g/d), physical activity (<3.0, 3.0-8.9, 9.0-17.9, 18.0-26.9, ≥27.0 metabolic equivalent of task–h/wk), multivitamin use (yes/no), history of hypertension (yes/no), history of hypercholesterolemia (yes/no), in women postmenopausal status and menopausal hormone use (premenopausal, postmenopausal [no, past, or current hormone use]), total energy intake (kcal/d), family history of dementia (yes/no), history of depression (yes/no), census socioeconomic status (9-variable score, in quintiles), body mass index calculated as weight in kilograms divided by height in meters squared (<23, 23-25, 25-30, 30-35, ≥35), red meat, fruits and vegetables, nuts, soda, whole grains intake (in quintiles), and trans-fat. Pooled results were obtained by pooling the data sets of the cohorts and Cox proportional hazards model 3 was further stratified by cohort (sex). HR indicates hazard ratio.

eTable 1. Odds Ratios for Dementia-Related Mortality by APOE4 Allelic Dosage

eTable 2. Risk of Death With Dementia (Composite Outcome) According to Categories of Total Olive Oil

eTable 3. Joint Associations of Olive Oil Intake and AMED (A), and AHEI (B) With Dementia-Related Mortality Risk

eTable 4. Risk of Dementia-Related Mortality According to Categories of Total Olive Oil in the Genomic DNA Subsample

eFigure. Subgroup Analyses for 5g/d Increase in Olive Oil Intake With Dementia-Related Mortality Risk

eTable 5. Risk of Dementia-Related Mortality According to Categories of Total Olive Oil Without Stopping Diet Update Upon Report of Intermediate Non-Fatal Events

eTable 6. Risk of Dementia Mortality According to Categories of Total Olive Oil Applying a 4-Year Lag Period Between Dietary Intake and Dementia Mortality

eTable 7. Risk of Dementia-Related Mortality According to Categories of Total Olive Oil Adjusting for Other Covariates

eTable 8. Risk of Mortality From Dementia and Other Causes of Death According to Categories of Total Olive Oil Applying a Competing Risk Model

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Tessier A , Cortese M , Yuan C, et al. Consumption of Olive Oil and Diet Quality and Risk of Dementia-Related Death. JAMA Netw Open. 2024;7(5):e2410021. doi:10.1001/jamanetworkopen.2024.10021

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Consumption of Olive Oil and Diet Quality and Risk of Dementia-Related Death

• 1 Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, Massachusetts
• 2 School of Public Health, the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
• 3 Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts
• 4 Channing Division of Network Medicine, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
• 5 Department of Public Health and Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark

Question   Is the long-term consumption of olive oil associated with dementia-related death risk?

Findings   In a prospective cohort study of 92 383 adults observed over 28 years, the consumption of more than 7 g/d of olive oil was associated with a 28% lower risk of dementia-related death compared with never or rarely consuming olive oil, irrespective of diet quality.

Meaning   These results suggest that olive oil intake represents a potential strategy to reduce dementia mortality risk.

Importance   Age-standardized dementia mortality rates are on the rise. Whether long-term consumption of olive oil and diet quality are associated with dementia-related death is unknown.

Objective   To examine the association of olive oil intake with the subsequent risk of dementia-related death and assess the joint association with diet quality and substitution for other fats.

Design, Setting, and Participants   This prospective cohort study examined data from the Nurses’ Health Study (NHS; 1990-2018) and Health Professionals Follow-Up Study (HPFS; 1990-2018). The population included women from the NHS and men from the HPFS who were free of cardiovascular disease and cancer at baseline. Data were analyzed from May 2022 to July 2023.

Exposures   Olive oil intake was assessed every 4 years using a food frequency questionnaire and categorized as (1) never or less than once per month, (2) greater than 0 to less than or equal to 4.5 g/d, (3) greater than 4.5 g/d to less than or equal to 7 g/d, and (4) greater than 7 g/d. Diet quality was based on the Alternative Healthy Eating Index and Mediterranean Diet score.

Main Outcome and Measure   Dementia death was ascertained from death records. Multivariable Cox proportional hazards regressions were used to estimate hazard ratios (HRs) and 95% CIs adjusted for confounders including genetic, sociodemographic, and lifestyle factors.

Results   Of 92 383 participants, 60 582 (65.6%) were women and the mean (SD) age was 56.4 (8.0) years. During 28 years of follow-up (2 183 095 person-years), 4751 dementia-related deaths occurred. Individuals who were homozygous for the apolipoprotein ε4 ( APOE ε4 ) allele were 5 to 9 times more likely to die with dementia. Consuming at least 7 g/d of olive oil was associated with a 28% lower risk of dementia-related death (adjusted pooled HR, 0.72 [95% CI, 0.64-0.81]) compared with never or rarely consuming olive oil ( P for trend < .001); results were consistent after further adjustment for APOE ε4 . No interaction by diet quality scores was found. In modeled substitution analyses, replacing 5 g/d of margarine and mayonnaise with the equivalent amount of olive oil was associated with an 8% (95% CI, 4%-12%) to 14% (95% CI, 7%-20%) lower risk of dementia mortality. Substitutions for other vegetable oils or butter were not significant.

Conclusions and Relevance   In US adults, higher olive oil intake was associated with a lower risk of dementia-related mortality, irrespective of diet quality. Beyond heart health, the findings extend the current dietary recommendations of choosing olive oil and other vegetable oils for cognitive-related health.

One-third of older adults die with Alzheimer disease or another dementia. 1 While deaths from diseases such as stroke and heart disease have been decreasing over the past 20 years, age-standardized dementia mortality rates have been on the rise. 2 The Mediterranean diet has gained in popularity owing to its recognized, multifaceted health benefits, particularly on cardiovascular outcomes. 3 Accruing evidence suggests this dietary pattern also has a beneficial effect on cognitive health. 4 As part of the Mediterranean diet, olive oil may exert anti-inflammatory and neuroprotective effects due to its high content of monounsaturated fatty acids and other compounds with antioxidant properties such as vitamin E and polyphenols. 5 A substudy conducted as part of the Prevencion con Dieta Mediterranea (PREDIMED) randomized trial provided evidence that higher intake of olive oil for 6.5 years combined with adherence to a Mediterranean diet was protective of cognitive decline when compared with a low-fat control diet. 6 - 8

Given that most previous studies on olive oil consumption and cognition were conducted in Mediterranean countries, 7 - 10 studying the US population, where olive oil consumption is generally lower, could offer unique insights. Recently, we showed that olive oil consumption was associated with a lower risk of total and cause-specific mortality in large US prospective cohort studies, including a 29% (95% CI, 22%-36%) lower risk for neurodegenerative disease mortality in participants who consumed more than 7 g/d of olive oil compared with little or none. 11 However, this previous analysis was not designed to examine the association of olive oil and diet quality with dementia-related mortality, and therefore the latter remains unclear.

In this study, we examined the association between total olive oil consumption and the subsequent risk of dementia-related mortality in 2 large prospective studies of US women and men. Additionally, we evaluated the joint associations of diet quality (adherence to the Mediterranean diet and Alternative Healthy Eating Index [AHEI] score) and olive oil consumption with the risk of dementia-related mortality. We also estimated the difference in the risk of dementia-related mortality when other dietary fats were substituted with an equivalent amount of olive oil.

Analyses were performed in 2 large US prospective cohorts: the Nurses’ Health Study I (NHS) and the Health Professionals Follow-Up Study (HPFS). The NHS was initiated in 1976 and recruited 121 700 US female registered nurses aged 30 to 55 years. 12 The HPFS was established in 1986 and included 51 525 male health professionals aged 40 to 75 years. 13 The cohorts have been described elsewhere. 12 , 13 Lifestyle factors and medical history were assessed biennially through mailed questionnaires, with a follow-up rate greater than 90%. Baseline for this analysis was 1990, which is when the food frequency questionnaires (FFQs) first included information on olive oil consumption.

Participants with a history of cardiovascular disease (CVD) or cancer at baseline, with missing data on olive oil consumption, or who reported implausible total energy intakes (<500 or >3500 kcal/d for women and <800 or >4200 kcal/d for men) were excluded. The completion of the questionnaire self-selected cognitively highly functioning women and men. In total, 60 582 women and 31 801 men were included. The study protocol was approved by the institutional review boards of the Brigham and Women’s Hospital and Harvard T.H. Chan School of Public Health, which deemed the participants’ completion of the questionnaire to be considered as implied consent. This report followed the Strengthening the Reporting of Observational Studies in Epidemiology ( STROBE ) reporting guideline.

Dietary intake was measured using a validated greater than 130-item FFQ administered in 1990 and every 4 years thereafter. The validity and reliability of the FFQ have been described previously. 14 Participants were asked how frequently they consumed specific foods, including types of fats and oils used for cooking or added to meals in the past 12 months. Total olive oil intake was determined by summing up answers to 3 questions related to olive oil consumption (ie, olive oil used for salad dressings, olive oil added to food or bread, and olive oil used for baking and frying at home). The equivalent of 1 tablespoon of olive oil was considered to be 13.5 g. Intakes of other fats and nutrients were calculated using the United States Department of Agriculture and Harvard University Food Composition Database, 15 and biochemical analyses. The nutritional composition of olive oil and other types of fat, as well as trends of types of fat intake in the NHS and HPFS, have been reported previously. 11

Adherence to the Mediterranean diet was assessed using a modified version of the 9-point Alternative Mediterranean index (AMED) score. 16 Adherence to the AHEI (0-110), previously associated with lower risk of chronic disease, was also computed. 17 Higher scores indicated better overall diet quality.

The apolipoprotein E ε4 ( APOE ε4 ) allele is known to interfere with lipid and glucose metabolism such that it increases the risk of dementia. 18  APOE genotyping was conducted in a subset of 27 296 participants. Blood samples were collected between 1989 and 1990 in the NHS and between 1993 and 1995 in the HPFS. NHS participants who had not provided blood samples were invited to contribute buccal samples from 2002 to 2004. DNA was extracted with the ReturPureGene DNA Isolation Kit (Gentra Systems). The APOE genotype was determined using a Taqman Assay (Applied Biosystems) 19 in 5069 participants, and through imputation from multiple genome-wide association studies, 20 which has shown high accuracy, 20 in the remaining subset.

Deaths were ascertained from state vital statistics records and the National Death Index or by reports from next of kin or the postal authorities. The follow-up for mortality exceeded 98% in these cohorts. Dementia deaths were determined by physician review of medical records, autopsy reports, or death certificates. Dementia deaths were those in which dementia was listed as the underlying cause of death, or as a contributing cause of death, or as reported by the family, in the absence of a more likely cause. The International Classification of Diseases, Eighth Revision (ICD-8) was used in the NHS and ICD-9 in the HPFS, which were the revisions used at the inception of those cohorts. Dementia deaths included codes 290.0 (senile dementia, simple type), 290.1 (presenile dementia), and 331.0 (Alzheimer disease). To test the validity of the dementia mortality outcome, we examined the likelihood of dementia mortality by APOE ε4 allelic dosage (eTable 1 in Supplement 1 ). 18 A composite outcome was also created including both participants who reported having dementia during follow-up and later died, with those who had dementia reported on their death certificate.

Participants completed biennial questionnaires reporting updates on body weight, smoking, physical activity, multivitamin use, menopausal status, and postmenopausal hormone use in women, family history of dementia, self-report of chronic diseases, and ancestry. History of depression was identified based on antidepressive medication use and self-report of depression. Socioeconomic status (SES) was established through a composite score derived from home address details and various factors such as income, education, and housing; the composite score methods are described in a previous report. 21 Body mass index (BMI) was obtained by dividing the weight in kilograms by the height in meters squared.

In each cohort, age-stratified Cox proportional hazard models were used to evaluate the association of olive oil intake with dementia-related mortality. Participant person-time was calculated from baseline until end of follow-up (June 30, 2018, in NHS; January 31, 2018, in HPFS), loss to follow-up, or death, whichever came first. The cumulative average (mean) of olive oil intake from all available FFQs, from baseline until 2014 (or loss to follow-up or death), was used as the exposure. Because potential diet modifications following cancer or CVD diagnosis may not represent long-term diet, we ceased updating dietary variables upon report of these conditions. For missing covariates, we carried forward nonmissing values from previous questionnaires and assigned median values for continuous variables.

Participants were categorized by olive oil intake frequency: never or less than once per month (reference group), greater than 0 to less than or equal to 4.5 g/d, greater than 4.5 g/d to less than or equal to 7 g/d, and greater than 7 g/d. P values for linear trends were obtained using the Wald test on a continuous variable represented by the median intake of each category. Multivariable Cox proportional hazard models were used to estimate the hazard ratios (HRs) and 95% CIs for dementia mortality according to categories of olive oil intake, separately in each cohort. Participants were censored at death from causes other than dementia. Model 1 was stratified for age and calendar time. Multivariable model 2 was adjusted for Southern European/Mediterranean ancestry, married, living alone, smoking, alcohol intake, physical activity, multivitamin use, history of hypertension and hypercholesterolemia, in women postmenopausal status and menopausal hormone use, total energy intake, family history of dementia, history of depression, census SES, and BMI. Multivariable model 3 was further adjusted for intake of red meat, fruits and vegetables, nuts, soda, whole grains, and trans-fat, all indicative of diet quality.

In a secondary analysis we used the composite outcome for dementia-related deaths. We also repeated the main analysis in the genotyping subsample. We carried out mediation analyses to calculate the percentage of the association between olive oil intake and dementia-related mortality that is attributable to CVD, hypercholesterolemia, hypertension, and diabetes. We also performed stratified analyses by prespecified subgroups (eMethods in Supplement 1 ).

A joint analysis was performed to test whether olive oil intake (never or <1/mo, >0 to ≤7g/d, and >7g/d) and the AMED or the AHEI score (tertiles) combined as the exposure was associated with dementia mortality. In substitution analyses, we assessed the risk of dementia-related mortality by replacing 5 g/d of different fat sources, including margarine, mayonnaise, butter, and a combination of other vegetable oils (corn, safflower, soybean, and canola), with olive oil. Both continuous variables as 5-g/d increments were included in a multivariable model 3, mutually adjusted for other types of fat. The difference in the coefficients obtained for olive oil and the substituted fat provided the estimated HR and 95% CI for substituting 5 g/d of olive oil for an equivalent amount of the other fats.

Several exploratory sensitivity analyses were performed including a 4-year lagged analysis, analyses adjusting for other covariates, a cause-specific competing risk model and analyses excluding participants who self-reported having dementia at baseline (n = 12) (eMethods in Supplement 1 ). Analyses were performed from May 2022 to July 2023 using SAS version 9.4 (SAS Institute). All statistical tests were 2-sided with an α = .05.

Over 2 183 095 person-years of follow-up, this study documented a total of 4751 dementia deaths (3473 in NHS and 1278 in HPFS; 37 649 total deaths). Among 92 383 participants included at baseline in 1990, 60 582 (65.6%) were women, and the mean (SD) age was 56.4 (8.0) years. Mean (SD) olive oil intake was 1.3 (2.5) g/d in both NHS and HPFS; the mean (SD) adherence score for the Mediterranean diet was 4.5 (1.9) points in the NHS and 4.2 (1.9) points in the HPFS; and the mean (SD) AHEI diet quality score was 52.5 (11.1) points in the NHS and 53.4 (11.6) points in the HPFS.

Table 1 shows baseline characteristics of participants categorized by total olive oil intake. Participants with a higher olive oil intake (>7 g/d) at baseline had an overall higher caloric intake, but not a higher BMI, had better diet quality, had higher alcohol intake, were more physically active, and were less likely to smoke compared with those never consuming olive oil or less than once per month ( Table1 ). Individuals who were homozygous for the APOE ε4 allele were 5.5 to 9.4 times more likely to die with dementia compared with noncarriers for the APOE e4 allele (χ 2  P  < .001) (eTable 1 in Supplement 1 ).

Olive oil intake was inversely associated with dementia-related mortality in age-stratified and multivariable-adjusted models ( Table 2 ). Compared with participants with the lowest olive oil intake, the pooled HR for dementia-related death among participants with the highest olive oil intake (>7 g/d) was 0.72 (95% CI, 0.64-0.81), after adjusting for sociodemographic and lifestyle factors. The association between each 5-g increment in olive oil consumption with dementia-related death was also inverse and significant in the pooled analysis. The multivariable-adjusted HR for dementia-related death for the highest compared with the lowest olive oil intake (>7 g/d) was 0.67 (95% CI, 0.59-0.77) for women and 0.87 (95% CI, 0.69-1.09) for men ( Table 2 ). Olive oil intake in 5-g increments was inversely associated with dementia-related mortality in women (HR, 0.88 [95% CI, 0.84-0.93]), but not in men (HR, 0.96 [95% CI, 0.88-1.04]). Analyses remained consistent when using the composite outcome for death with dementia (eTable 2 in Supplement 2 ). In the genotyping subsample, the results remained unchanged after further adjusting for the APOE ε4 allelic genotype (multivariable-adjusted pooled HR comparing high vs low olive oil intake, 0.66 [95% CI, 0.54-0.81]; P for trend < .001) (eTable 4 in Supplement 1 ). Pooled mediation analyses found that CVD, hypercholesterolemia, hypertension, and diabetes did not significantly attenuate the association (unchanged HRs with and without adjusting for the intermediate; data not shown).

In joint analyses, participants with the highest olive oil intake had a lower risk for dementia-related mortality, irrespective of their AMED score (28% to 34% lower risk compared with participants in the combined low olive oil and high AMED) ( Figure 1 A; eTable 3 in Supplement 1 ) and of their AHEI (27% to 38% lower risk compared with participants with low olive oil and high AHEI) ( Figure 1 B; eTable 3 in Supplement 1 ).

Replacing 5 g/d of mayonnaise with 5 g/d of olive oil was associated with a 14% (95% CI, 7%-20%) lower risk of dementia-related mortality in pooled multivariable-adjusted models ( Figure 2 ). As for the substitution of 5 g/d of margarine with the equivalent amount of olive oil, we estimated an 8% (95% CI, 4%-12%) lower risk. Substitutions of other vegetable oils or butter with olive oil were not statistically significant.

Exploratory subgroup analyses (eFigure in Supplement 1 ) showed associations between higher olive oil intake and lower risk of dementia-related mortality across most subgroups. No statistically significant associations were found in participants with a family history of dementia, living alone, using a multivitamin, and in non– APOE ε4 carriers. Results from exploratory sensitivity analyses (eTables 5-8 in Supplement 1 ) were comparable with the findings from the main analysis (eResults in Supplement 1 ).

In 2 large US prospective cohorts of men and women, we found that participants who consumed more than 7 g/d of olive oil had 28% lower risk of dying from dementia compared with participants who never or rarely consumed olive oil. This association remained significant after adjustment for diet quality scores including adherence to the Mediterranean diet. We estimated that substituting 5 g/d of margarine and mayonnaise with olive oil was associated with significantly lower dementia-related death risk, but not when substituting butter and other vegetable oils. These findings provide evidence to support dietary recommendations advocating for the use of olive oil and other vegetable oils as a potential strategy to maintain overall health and prevent dementia.

In the NHS and HPFS, a lower risk of neurodegenerative disease mortality, including dementia mortality, was observed with higher olive oil consumption (HR, 0.81 [95% CI, 0.78-0.84]). 11 Evidence that pertains to cognitive decline or incident dementia is more widely available than it is for dementia mortality. 6 , 22 In the French Three-City Study (n = 6947), participants with the highest olive oil intake were 17% (95% CI, 1%-29%) less likely to experience a 4-year cognitive decline related to visual memory, but no association was found for verbal fluency (odds ratio [OR], 0.85 [95% CI, 0.70-1.03]). 22 Furthermore, participants with a higher intake of olive oil (moderate or intensive vs never) had a lower risk of verbal fluency and visual memory cognitive impairment. Potential sex differences were not investigated. In the PREDIMED trial, which supplemented a Mediterranean-style diet with extra-virgin olive oil (1 L/wk/household) or nuts (30 g/d), 23 the authors investigated cognitive effects and status in 285 and 522 cognitively healthy participants using global and in-depth neuropsychological battery testing. Although the study was not originally designed for cognitive outcomes and the effect of olive oil cannot be isolated, after 6.5 years, the olive oil group exhibited improved cognitive performance in verbal fluency and memory tests compared with a low-fat diet (control), and they were less prone to develop mild cognitive impairment (OR, 0.34 [95% CI, 0.12-0.97]; n = 285). 6 Global cognitive performance was higher in both the olive oil and the nut groups compared with the control post trial (n = 522). 8 These studies were conducted in Europe, in populations with typically higher olive oil intake compared with US populations.

Observational studies and some trials have consistently found associations between following diets such as the Mediterranean, DASH, MIND, and AHEI, and prudent patterns to healthier brain structure, 24 reduced cognitive impairment and Alzheimer risk, and improved cognitive function. 4 In our study, those with the highest olive oil intake (>7 g/d) had the lowest dementia-related death risk compared with those with minimal intake (never or less than once per month), regardless of diet quality. This highlights a potentially specific role for olive oil. Still, the group with both high AHEI scores and high olive oil intake exhibited the lowest dementia mortality risk (HR, 0.68 [95% CI, 0.58-0.79]; reference: low AHEI score and low olive oil intake), suggesting that combining higher diet quality with higher olive oil intake may confer enhanced benefit.

Olive oil consumption may lower dementia mortality by improving vascular health. 18 Several clinical trials support the effect of olive oil in reducing CVD via improved endothelial function, coagulation, lipid metabolism, oxidative stress, platelet aggregation and decreased inflammation. 25 Nonetheless, the results of our study remained independent of hypertension and hypercholesterolemia. Mild cognitive impairment, Alzheimer disease, and related dementias were associated with abnormal blood brain barrier permeability, possibly allowing the crossing of neurotoxic molecules into the brain. 26 Mechanistical evidence from animal 27 - 29 and human studies 9 , 30 have shown that phenolic compounds in olive oil, particularly extra-virgin olive oil, may attenuate inflammation, oxidative stress and restore blood brain barrier function, thereby reducing brain amyloid-β and tau-related pathologies and improving cognitive function. However, incident CVD, hypercholesterolemia, hypertension, and diabetes were not significant mediators of the association between olive oil intake and dementia-related death in our study.

The association was significant in both sexes but did not remain in men after full adjustment of the model. Some previous research has reported cognitive-related sex differences. Evidence from trials also showed sex- and/or gender-specific responses to lifestyle interventions for preventing cognitive decline, possibly due to differences in brain structure, hormones (sex) and social factors (gender). 31 Olive oil intake may be protective of dementia and related mortality, particularly in women. Nonetheless, we did not observe significant heterogeneity or interaction of cohort by olive oil intake on the risk of fatal dementia. Sex and gender differences should be carefully considered in future studies examining the association or effect of olive oil on cognitive-related outcomes to improve our understanding.

We found that using olive oil instead of margarine and mayonnaise, but not butter and other vegetable oils, was associated with a lower risk of dementia-related death. At the time of the study, margarine and mayonnaise contained considerable levels of hydrogenated trans-fats. The latter were strongly associated with all-cause mortality, CVD, type 2 diabetes, and dementia, 32 , 33 which may explain the lower dementia-related death risk observed when replacing it with olive oil. The US Food and Drug Administration banned manufacturers from adding partially hydrogenated oils to foods in 2020. 34 Future studies examining intake of trans-fat–free margarine will be informative. Although the substitution of butter with olive oil was found to be associated with a lower risk of type 2 diabetes, CVD, and total mortality, 11 we did not find an association with the risk of dementia mortality. Although these previous studies did not examine the associations for butter per se, intake of regular fat dairy products, including cheese, yogurt, and milk, was reported to be either not associated or inversely associated with lower cognitive function, cognitive decline, and dementia. 35 - 37

Our cohort analyses include several strengths, namely the long follow-up period and large sample size with a high number of dementia death cases. Also, we included genotyping of the APOE ε4 allele in a large subsample of participants to reduce potential confounding attributed to this well-known risk factor for Alzheimer disease. Additionally, our repeated diet measurements, weight, and lifestyle variables permitted us to account for long-term olive oil intake and confounding factors. Furthermore, the use of dietary cumulative average updates reduced random measurement error by considering within-person variations in intake.

This study has limitations. The possibility of reverse causation cannot be excluded due to the observational nature of our study. However, the 4-year lagged analysis results, consistent with the primary analysis, suggest that olive oil intake is predictive of dementia mortality rather than a consequence of premorbid dementia. While it is plausible that higher olive oil intake could be indicative of a healthier diet and higher SES, our results remained consistent after accounting for the latter. Despite adjusting for key covariates, residual confounding may remain due to unmeasured factors. Also, our study was conducted among health professionals. While this minimizes the potential confounding effects of socioeconomic factors and likely increases reporting due to a high level of education, this may also limit generalizability. Our population was predominantly of non-Hispanic White participants, limiting generalizability to more diverse populations. Additionally, we could not differentiate among various types of olive oil that differ in their polyphenols and other nonlipid bioactive compounds content.

This study found that in US adults, particularly women, consuming more olive oil was associated with lower risk of dementia-related mortality, regardless of diet quality. Substituting olive oil intake for margarine and mayonnaise was associated with lower risk of dementia mortality and may be a potential strategy to improve longevity free of dementia. These findings extend the current dietary recommendations of choosing olive oil and other vegetable oils to the context of cognitive health and related mortality.

Accepted for Publication: March 6, 2024.

Published: May 6, 2024. doi:10.1001/jamanetworkopen.2024.10021

Open Access: This is an open access article distributed under the terms of the CC-BY License . © 2024 Tessier AJ et al. JAMA Network Open .

Corresponding Authors: Anne-Julie Tessier, RD, PhD ( [email protected] ), and Marta Guasch-Ferré, PhD ( [email protected] ), Department of Nutrition, Harvard T.H. Chan School of Public Health, 655 Huntington Ave, Bldg 2, Boston, MA 02115.

Author Contributions: Drs Tessier and Guasch-Ferré had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: Tessier, Chavarro, Hu, Willett, Guasch-Ferré.

Acquisition, analysis, or interpretation of data: Tessier, Cortese, Yuan, Bjornevik, Ascherio, Wang, Chavarro, Stampfer, Willett, Guasch-Ferré.

Drafting of the manuscript: Tessier.

Critical review of the manuscript for important intellectual content: Tessier, Cortese, Yuan, Bjornevik, Ascherio, Wang, Chavarro, Stampfer, Hu, Willett, Guasch-Ferré.

Statistical analysis: Tessier, Cortese, Wang, Willett, Guasch-Ferré.

Obtained funding: Chavarro, Stampfer, Hu, Guasch-Ferré.

Administrative, technical, or material support: Cortese, Yuan, Stampfer, Hu.

Supervision: Chavarro, Hu, Guasch-Ferré.

Conflict of Interest Disclosures: Dr Cortese reported a speaker honorarium from Roche outside the submitted work. Dr Ascherio reported receiving speaker honoraria from WebMD, Prada Foundation, Biogen, Moderna, Merck, Roche, and Glaxo-Smith-Kline. No other disclosures were reported.

Funding/Support: This study is supported by the research grant R21 AG070375 from the National Institutes of Health to Dr Guasch-Ferré. The NHS, NHSII and HPFS are supported by grants from the National Institutes of Health (UM1 CA186107, P01 CA87969, U01 CA167552, P30 DK046200, HL034594, HL088521, HL35464, HL60712). Dr Tessier is supported by the Canadian Institutes of Health Research (CIHR) Postdoctoral Fellowship Award. Dr Guasch-Ferré is supported the Novo Nordisk Foundation grant NNF23SA0084103.

Role of the Funder/Sponsor: The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Data Sharing Statement: See Supplement 2 .

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