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Validity, reliability, and generalizability in qualitative research

Lawrence leung.

1 Department of Family Medicine, Queen's University, Kingston, Ontario, Canada

2 Centre of Studies in Primary Care, Queen's University, Kingston, Ontario, Canada

In general practice, qualitative research contributes as significantly as quantitative research, in particular regarding psycho-social aspects of patient-care, health services provision, policy setting, and health administrations. In contrast to quantitative research, qualitative research as a whole has been constantly critiqued, if not disparaged, by the lack of consensus for assessing its quality and robustness. This article illustrates with five published studies how qualitative research can impact and reshape the discipline of primary care, spiraling out from clinic-based health screening to community-based disease monitoring, evaluation of out-of-hours triage services to provincial psychiatric care pathways model and finally, national legislation of core measures for children's healthcare insurance. Fundamental concepts of validity, reliability, and generalizability as applicable to qualitative research are then addressed with an update on the current views and controversies.

Nature of Qualitative Research versus Quantitative Research

The essence of qualitative research is to make sense of and recognize patterns among words in order to build up a meaningful picture without compromising its richness and dimensionality. Like quantitative research, the qualitative research aims to seek answers for questions of “how, where, when who and why” with a perspective to build a theory or refute an existing theory. Unlike quantitative research which deals primarily with numerical data and their statistical interpretations under a reductionist, logical and strictly objective paradigm, qualitative research handles nonnumerical information and their phenomenological interpretation, which inextricably tie in with human senses and subjectivity. While human emotions and perspectives from both subjects and researchers are considered undesirable biases confounding results in quantitative research, the same elements are considered essential and inevitable, if not treasurable, in qualitative research as they invariable add extra dimensions and colors to enrich the corpus of findings. However, the issue of subjectivity and contextual ramifications has fueled incessant controversies regarding yardsticks for quality and trustworthiness of qualitative research results for healthcare.

Impact of Qualitative Research upon Primary Care

In many ways, qualitative research contributes significantly, if not more so than quantitative research, to the field of primary care at various levels. Five qualitative studies are chosen to illustrate how various methodologies of qualitative research helped in advancing primary healthcare, from novel monitoring of chronic obstructive pulmonary disease (COPD) via mobile-health technology,[ 1 ] informed decision for colorectal cancer screening,[ 2 ] triaging out-of-hours GP services,[ 3 ] evaluating care pathways for community psychiatry[ 4 ] and finally prioritization of healthcare initiatives for legislation purposes at national levels.[ 5 ] With the recent advances of information technology and mobile connecting device, self-monitoring and management of chronic diseases via tele-health technology may seem beneficial to both the patient and healthcare provider. Recruiting COPD patients who were given tele-health devices that monitored lung functions, Williams et al. [ 1 ] conducted phone interviews and analyzed their transcripts via a grounded theory approach, identified themes which enabled them to conclude that such mobile-health setup and application helped to engage patients with better adherence to treatment and overall improvement in mood. Such positive findings were in contrast to previous studies, which opined that elderly patients were often challenged by operating computer tablets,[ 6 ] or, conversing with the tele-health software.[ 7 ] To explore the content of recommendations for colorectal cancer screening given out by family physicians, Wackerbarth, et al. [ 2 ] conducted semi-structure interviews with subsequent content analysis and found that most physicians delivered information to enrich patient knowledge with little regard to patients’ true understanding, ideas, and preferences in the matter. These findings suggested room for improvement for family physicians to better engage their patients in recommending preventative care. Faced with various models of out-of-hours triage services for GP consultations, Egbunike et al. [ 3 ] conducted thematic analysis on semi-structured telephone interviews with patients and doctors in various urban, rural and mixed settings. They found that the efficiency of triage services remained a prime concern from both users and providers, among issues of access to doctors and unfulfilled/mismatched expectations from users, which could arouse dissatisfaction and legal implications. In UK, a care pathways model for community psychiatry had been introduced but its benefits were unclear. Khandaker et al. [ 4 ] hence conducted a qualitative study using semi-structure interviews with medical staff and other stakeholders; adopting a grounded-theory approach, major themes emerged which included improved equality of access, more focused logistics, increased work throughput and better accountability for community psychiatry provided under the care pathway model. Finally, at the US national level, Mangione-Smith et al. [ 5 ] employed a modified Delphi method to gather consensus from a panel of nominators which were recognized experts and stakeholders in their disciplines, and identified a core set of quality measures for children's healthcare under the Medicaid and Children's Health Insurance Program. These core measures were made transparent for public opinion and later passed on for full legislation, hence illustrating the impact of qualitative research upon social welfare and policy improvement.

Overall Criteria for Quality in Qualitative Research

Given the diverse genera and forms of qualitative research, there is no consensus for assessing any piece of qualitative research work. Various approaches have been suggested, the two leading schools of thoughts being the school of Dixon-Woods et al. [ 8 ] which emphasizes on methodology, and that of Lincoln et al. [ 9 ] which stresses the rigor of interpretation of results. By identifying commonalities of qualitative research, Dixon-Woods produced a checklist of questions for assessing clarity and appropriateness of the research question; the description and appropriateness for sampling, data collection and data analysis; levels of support and evidence for claims; coherence between data, interpretation and conclusions, and finally level of contribution of the paper. These criteria foster the 10 questions for the Critical Appraisal Skills Program checklist for qualitative studies.[ 10 ] However, these methodology-weighted criteria may not do justice to qualitative studies that differ in epistemological and philosophical paradigms,[ 11 , 12 ] one classic example will be positivistic versus interpretivistic.[ 13 ] Equally, without a robust methodological layout, rigorous interpretation of results advocated by Lincoln et al. [ 9 ] will not be good either. Meyrick[ 14 ] argued from a different angle and proposed fulfillment of the dual core criteria of “transparency” and “systematicity” for good quality qualitative research. In brief, every step of the research logistics (from theory formation, design of study, sampling, data acquisition and analysis to results and conclusions) has to be validated if it is transparent or systematic enough. In this manner, both the research process and results can be assured of high rigor and robustness.[ 14 ] Finally, Kitto et al. [ 15 ] epitomized six criteria for assessing overall quality of qualitative research: (i) Clarification and justification, (ii) procedural rigor, (iii) sample representativeness, (iv) interpretative rigor, (v) reflexive and evaluative rigor and (vi) transferability/generalizability, which also double as evaluative landmarks for manuscript review to the Medical Journal of Australia. Same for quantitative research, quality for qualitative research can be assessed in terms of validity, reliability, and generalizability.

Validity in qualitative research means “appropriateness” of the tools, processes, and data. Whether the research question is valid for the desired outcome, the choice of methodology is appropriate for answering the research question, the design is valid for the methodology, the sampling and data analysis is appropriate, and finally the results and conclusions are valid for the sample and context. In assessing validity of qualitative research, the challenge can start from the ontology and epistemology of the issue being studied, e.g. the concept of “individual” is seen differently between humanistic and positive psychologists due to differing philosophical perspectives:[ 16 ] Where humanistic psychologists believe “individual” is a product of existential awareness and social interaction, positive psychologists think the “individual” exists side-by-side with formation of any human being. Set off in different pathways, qualitative research regarding the individual's wellbeing will be concluded with varying validity. Choice of methodology must enable detection of findings/phenomena in the appropriate context for it to be valid, with due regard to culturally and contextually variable. For sampling, procedures and methods must be appropriate for the research paradigm and be distinctive between systematic,[ 17 ] purposeful[ 18 ] or theoretical (adaptive) sampling[ 19 , 20 ] where the systematic sampling has no a priori theory, purposeful sampling often has a certain aim or framework and theoretical sampling is molded by the ongoing process of data collection and theory in evolution. For data extraction and analysis, several methods were adopted to enhance validity, including 1 st tier triangulation (of researchers) and 2 nd tier triangulation (of resources and theories),[ 17 , 21 ] well-documented audit trail of materials and processes,[ 22 , 23 , 24 ] multidimensional analysis as concept- or case-orientated[ 25 , 26 ] and respondent verification.[ 21 , 27 ]

Reliability

In quantitative research, reliability refers to exact replicability of the processes and the results. In qualitative research with diverse paradigms, such definition of reliability is challenging and epistemologically counter-intuitive. Hence, the essence of reliability for qualitative research lies with consistency.[ 24 , 28 ] A margin of variability for results is tolerated in qualitative research provided the methodology and epistemological logistics consistently yield data that are ontologically similar but may differ in richness and ambience within similar dimensions. Silverman[ 29 ] proposed five approaches in enhancing the reliability of process and results: Refutational analysis, constant data comparison, comprehensive data use, inclusive of the deviant case and use of tables. As data were extracted from the original sources, researchers must verify their accuracy in terms of form and context with constant comparison,[ 27 ] either alone or with peers (a form of triangulation).[ 30 ] The scope and analysis of data included should be as comprehensive and inclusive with reference to quantitative aspects if possible.[ 30 ] Adopting the Popperian dictum of falsifiability as essence of truth and science, attempted to refute the qualitative data and analytes should be performed to assess reliability.[ 31 ]

Generalizability

Most qualitative research studies, if not all, are meant to study a specific issue or phenomenon in a certain population or ethnic group, of a focused locality in a particular context, hence generalizability of qualitative research findings is usually not an expected attribute. However, with rising trend of knowledge synthesis from qualitative research via meta-synthesis, meta-narrative or meta-ethnography, evaluation of generalizability becomes pertinent. A pragmatic approach to assessing generalizability for qualitative studies is to adopt same criteria for validity: That is, use of systematic sampling, triangulation and constant comparison, proper audit and documentation, and multi-dimensional theory.[ 17 ] However, some researchers espouse the approach of analytical generalization[ 32 ] where one judges the extent to which the findings in one study can be generalized to another under similar theoretical, and the proximal similarity model, where generalizability of one study to another is judged by similarities between the time, place, people and other social contexts.[ 33 ] Thus said, Zimmer[ 34 ] questioned the suitability of meta-synthesis in view of the basic tenets of grounded theory,[ 35 ] phenomenology[ 36 ] and ethnography.[ 37 ] He concluded that any valid meta-synthesis must retain the other two goals of theory development and higher-level abstraction while in search of generalizability, and must be executed as a third level interpretation using Gadamer's concepts of the hermeneutic circle,[ 38 , 39 ] dialogic process[ 38 ] and fusion of horizons.[ 39 ] Finally, Toye et al. [ 40 ] reported the practicality of using “conceptual clarity” and “interpretative rigor” as intuitive criteria for assessing quality in meta-ethnography, which somehow echoed Rolfe's controversial aesthetic theory of research reports.[ 41 ]

Food for Thought

Despite various measures to enhance or ensure quality of qualitative studies, some researchers opined from a purist ontological and epistemological angle that qualitative research is not a unified, but ipso facto diverse field,[ 8 ] hence any attempt to synthesize or appraise different studies under one system is impossible and conceptually wrong. Barbour argued from a philosophical angle that these special measures or “technical fixes” (like purposive sampling, multiple-coding, triangulation, and respondent validation) can never confer the rigor as conceived.[ 11 ] In extremis, Rolfe et al. opined from the field of nursing research, that any set of formal criteria used to judge the quality of qualitative research are futile and without validity, and suggested that any qualitative report should be judged by the form it is written (aesthetic) and not by the contents (epistemic).[ 41 ] Rolfe's novel view is rebutted by Porter,[ 42 ] who argued via logical premises that two of Rolfe's fundamental statements were flawed: (i) “The content of research report is determined by their forms” may not be a fact, and (ii) that research appraisal being “subject to individual judgment based on insight and experience” will mean those without sufficient experience of performing research will be unable to judge adequately – hence an elitist's principle. From a realism standpoint, Porter then proposes multiple and open approaches for validity in qualitative research that incorporate parallel perspectives[ 43 , 44 ] and diversification of meanings.[ 44 ] Any work of qualitative research, when read by the readers, is always a two-way interactive process, such that validity and quality has to be judged by the receiving end too and not by the researcher end alone.

In summary, the three gold criteria of validity, reliability and generalizability apply in principle to assess quality for both quantitative and qualitative research, what differs will be the nature and type of processes that ontologically and epistemologically distinguish between the two.

Source of Support: Nil.

Conflict of Interest: None declared.

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  • Helen Noble 1 ,
  • Joanna Smith 2
  • 1 School of Nursing and Midwifery, Queens's University Belfast , Belfast , UK
  • 2 School of Human and Health Sciences, University of Huddersfield , Huddersfield , UK
  • Correspondence to Dr Helen Noble School of Nursing and Midwifery, Queens's University Belfast, Medical Biology Centre, 97 Lisburn Rd, Belfast BT9 7BL, UK; helen.noble{at}qub.ac.uk

https://doi.org/10.1136/eb-2015-102054

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Evaluating the quality of research is essential if findings are to be utilised in practice and incorporated into care delivery. In a previous article we explored ‘bias’ across research designs and outlined strategies to minimise bias. 1 The aim of this article is to further outline rigour, or the integrity in which a study is conducted, and ensure the credibility of findings in relation to qualitative research. Concepts such as reliability, validity and generalisability typically associated with quantitative research and alternative terminology will be compared in relation to their application to qualitative research. In addition, some of the strategies adopted by qualitative researchers to enhance the credibility of their research are outlined.

Are the terms reliability and validity relevant to ensuring credibility in qualitative research?

Although the tests and measures used to establish the validity and reliability of quantitative research cannot be applied to qualitative research, there are ongoing debates about whether terms such as validity, reliability and generalisability are appropriate to evaluate qualitative research. 2–4 In the broadest context these terms are applicable, with validity referring to the integrity and application of the methods undertaken and the precision in which the findings accurately reflect the data, while reliability describes consistency within the employed analytical procedures. 4 However, if qualitative methods are inherently different from quantitative methods in terms of philosophical positions and purpose, then alterative frameworks for establishing rigour are appropriate. 3 Lincoln and Guba 5 offer alternative criteria for demonstrating rigour within qualitative research namely truth value, consistency and neutrality and applicability. Table 1 outlines the differences in terminology and criteria used to evaluate qualitative research.

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Terminology and criteria used to evaluate the credibility of research findings

What strategies can qualitative researchers adopt to ensure the credibility of the study findings?

Unlike quantitative researchers, who apply statistical methods for establishing validity and reliability of research findings, qualitative researchers aim to design and incorporate methodological strategies to ensure the ‘trustworthiness’ of the findings. Such strategies include:

Accounting for personal biases which may have influenced findings; 6

Acknowledging biases in sampling and ongoing critical reflection of methods to ensure sufficient depth and relevance of data collection and analysis; 3

Meticulous record keeping, demonstrating a clear decision trail and ensuring interpretations of data are consistent and transparent; 3 , 4

Establishing a comparison case/seeking out similarities and differences across accounts to ensure different perspectives are represented; 6 , 7

Including rich and thick verbatim descriptions of participants’ accounts to support findings; 7

Demonstrating clarity in terms of thought processes during data analysis and subsequent interpretations 3 ;

Engaging with other researchers to reduce research bias; 3

Respondent validation: includes inviting participants to comment on the interview transcript and whether the final themes and concepts created adequately reflect the phenomena being investigated; 4

Data triangulation, 3 , 4 whereby different methods and perspectives help produce a more comprehensive set of findings. 8 , 9

Table 2 provides some specific examples of how some of these strategies were utilised to ensure rigour in a study that explored the impact of being a family carer to patients with stage 5 chronic kidney disease managed without dialysis. 10

Strategies for enhancing the credibility of qualitative research

In summary, it is imperative that all qualitative researchers incorporate strategies to enhance the credibility of a study during research design and implementation. Although there is no universally accepted terminology and criteria used to evaluate qualitative research, we have briefly outlined some of the strategies that can enhance the credibility of study findings.

  • Sandelowski M
  • Lincoln YS ,
  • Barrett M ,
  • Mayan M , et al
  • Greenhalgh T
  • Lingard L ,

Twitter Follow Joanna Smith at @josmith175 and Helen Noble at @helnoble

Competing interests None.

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The Significance of Validity and Reliability in Quantitative Research

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Key Takeaways:

  • Types of validity to consider during quantitative research include internal, external, construct, and statistical
  • Types of reliability that apply to quantitative research include test re-test, inter-rater, internal consistency, and parallel forms
  • There are numerous challenges to achieving validity and reliability in quantitative research, but the right techniques can help overcome them

Quantitative research is used to investigate and analyze data to draw meaningful conclusions. Validity and reliability are two critical concepts in quantitative analysis that ensure the accuracy and consistency of the research results. Validity refers to the extent to which the research measures what it intends to measure, while reliability refers to the consistency and reproducibility of the research results over time. Ensuring validity and reliability is crucial in conducting high-quality research, as it increases confidence in the findings and conclusions drawn from the data.

This article aims to provide an in-depth analysis of the significance of validity and reliability in quantitative research. It will explore the different types of validity and reliability, their interrelationships, and the associated challenges and limitations.

In this Article:

The role of validity in quantitative research, the role of reliability in quantitative research, validity and reliability: how they differ and interrelate, challenges and limitations of ensuring validity and reliability, overcoming challenges and limitations to achieve validity and reliability, explore trusted quantitative solutions.

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Validity is crucial in maintaining the credibility and reliability of quantitative research outcomes. Therefore, it is critical to establish that the variables being measured in a study align with the research objectives and accurately reflect the phenomenon being investigated.

Several types of validity apply to various study designs; let’s take a deeper look at each one below:

Internal validity is concerned with the extent to which a study establishes a causal relationship between the independent and dependent variables. In other words, internal validity determines whether the changes observed in the conditional variable result from changes in the independent variable or some other factor.

External validity refers to the degree to which the findings of a study can be generalized to other populations and contexts. External validity helps ensure the results of a study are not limited to the specific people or context in which the study was conducted.

Construct validity refers to the degree to which a research study accurately measures the theoretical construct it intends to measure. Construct validity helps provide alignment between the study’s measures and the theoretical concept it aims to investigate.

Finally, statistical validity refers to the accuracy of the statistical tests used to analyze the data. Establishing statistical validity provides confidence that the conclusions drawn from the data are reliable and accurate.

To safeguard the validity of a study, researchers must carefully design their research methodology, select appropriate measures, and control for extraneous variables that may impact the results. Validity is especially crucial in fields such as medicine, where inaccurate research findings can have severe consequences for patients and healthcare practices.

Ensuring the consistency and reproducibility of research outcomes over time is crucial in quantitative research, and this is where the concept of reliability comes into play. Reliability is vital to building trust in the research findings and their ability to be replicated in diverse contexts.

Similar to validity, multiple types of reliability are pertinent to different research designs. Let’s take a closer look at each of these types of reliability below:

Test-retest reliability refers to the consistency of the results obtained when the same test is administered to the same group of participants at different times. This type of reliability is essential when researchers need to administer the same test multiple times to assess changes in behavior or attitudes over time.

Inter-rater reliability refers to the results’ consistency when different raters or observers monitor the same behavior or phenomenon. This type of reliability is vital when researchers are required to rely on different individuals to rate or observe the same behavior or phenomenon.

Internal consistency reliability refers to the degree to which the items or questions in a test or questionnaire measure the same construct. This type of reliability is important in studies where researchers use multiple items or questions to assess a particular construct, such as knowledge or quality of life.

Lastly, parallel forms reliability refers to the consistency of the results obtained when two different versions of the same test are administered to the same group of participants. This type of reliability is important when researchers administer different versions of the same test to assess the consistency of the results.

Reliability in research is like the accuracy and consistency of a medical test. Just as a reliable medical test produces consistent and accurate results that physicians can trust to make informed decisions about patient care, a highly reliable study produces consistent and precise findings that researchers can trust to make knowledgeable conclusions about a particular phenomenon. To ensure reliability in a study, researchers must carefully select appropriate measures and establish protocols for administering the measures consistently. They must also take steps to control for extraneous variables that may impact the results.

Validity and reliability are two critical concepts in quantitative research that significantly determine the quality of research studies. While both terms are often used interchangeably, they refer to different aspects of research. Validity is the extent to which a research study measures what it claims to measure without being affected by extraneous factors or bias. In contrast, reliability is the degree to which the research results are consistent and stable over time and across different samples , methods, and evaluators.

Designing a research study that is both valid and reliable is essential for producing high-quality and trustworthy research findings. Finding this balance requires significant expertise, skill, and attention to detail. Ultimately, the goal is to produce research findings that are valid and reliable but also impactful and influential for the organization requesting them. Achieving this level of excellence requires a deep understanding of the nuances and complexities of research methodology and a commitment to excellence and rigor in all aspects of the research process.

Ensuring validity and reliability in quantitative research is not without its challenges. Some of the factors to consider include:

1. Measuring Complex Constructs or Variables One of the main challenges is the difficulty in accurately measuring complex constructs or variables. For instance, measuring constructs such as intelligence or personality can be complicated due to their multi-dimensional nature, and it can be challenging to capture all aspects accurately.

2. Limitations of Data Collection Instruments In addition, the measures or instruments used to collect data can also be limited in their sensitivity or specificity. This can impact the study’s validity and reliability, as accurate and precise measures can lead to incorrect conclusions and unreliable results. For example, a scale that measures depression but does not include all relevant symptoms may not accurately capture the construct being studied.

3. Sources of Error and Bias in Data Collection The data collection process itself can introduce sources of error or bias, which can impact the validity and reliability of the study. For instance, measurement errors can occur due to the limitations of the measuring instrument or human error during data collection. In addition, response bias can arise when participants provide socially desirable answers, while sampling bias can occur when the sample is not representative of the studied population.

4. The Complexity of Achieving Meaningful and Accurate Research Findings There are also some limitations to validity and reliability in research studies. For example, achieving internal validity by controlling for extraneous variables may only sometimes ensure external validity or the ability to generalize findings to other populations or settings. This can be a limitation for researchers who wish to apply their findings to a larger population or different contexts.

Additionally, while reliability is essential for producing consistent and reproducible results, it does not guarantee the accuracy or truth of the findings. This means that even if a study has reliable results, it may still need to be revised in terms of accuracy. These limitations remind us that research is a complex process, and achieving validity and reliability is just one part of the giant puzzle of producing accurate and meaningful research.

Researchers can adopt various measures and techniques to overcome the challenges and limitations in ensuring validity and reliability in research studies.

One such approach is to use multiple measures or instruments to assess the same construct. In addition, various steps can help identify commonalities and differences across measures, thereby providing a more comprehensive understanding of the construct being studied.

Inter-rater reliability checks can also be conducted to ensure different raters or observers consistently interpret and rate the same data. This can reduce measurement errors and improve the reliability of the results. Additionally, data-cleaning techniques can be used to identify and remove any outliers or errors in the data.

Finally, researchers can use appropriate statistical methods to assess the validity and reliability of their measures. For example, factor analysis identifies the underlying factors contributing to the construct being studied, while test-retest reliability helps evaluate the consistency of results over time. By adopting these measures and techniques, researchers can crease t their findings’ overall quality and usefulness.

The backbone of any quantitative research lies in the validity and reliability of the data collected. These factors ensure the data accurately reflects the intended research objectives and is consistent and reproducible. By carefully balancing the interrelationship between validity and reliability and using appropriate techniques to overcome challenges, researchers protect the credibility and impact of their work. This is essential in producing high-quality research that can withstand scrutiny and drive progress.

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Understanding validity and reliability from qualitative and quantitative research traditions

Main article content.

Educational constructs change over time to reflect developments in research and educational approaches. To illustrate the process, this article aims to examine validity and reliability, which are important concepts to justify research quality. Originally, validity and reliability were applied to quantitative research. However, these criteria can not be equally applied to qualitative research studies which differ in terms of their theoretical foundations and research aims. The unclear use of these concepts might lead to inappropriate research design or evaluation. This paper, therefore, first examines two different theoretical foundations underlying these two research traditions. It then analyses the subtle variations to clarify the notions of reliability and validity. Some implications are made for researchers to flexibly employ these criteria to enhance their research rigor.

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validity, reliability, qualitative research, quantitative research

Qualitative Researcher Dr Kriukow

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Validity and reliability in qualitative research.

validity and reliability in qualitative and quantitative research

What is Validity and Reliability in Qualitative research?

In Quantitative research, reliability refers to consistency of certain measurements, and validity – to whether these measurements “measure what they are supposed to measure”. Things are slightly different, however, in Qualitative research.

Reliability in qualitative studies is mostly a matter of “being thorough, careful and honest in carrying out the research” (Robson, 2002: 176). In qualitative interviews, this issue relates to a number of practical aspects of the process of interviewing, including the wording of interview questions, establishing rapport with the interviewees and considering ‘power relationship’ between the interviewer and the participant (e.g. Breakwell, 2000; Cohen et al., 2007; Silverman, 1993).

What seems more relevant when discussing qualitative studies is their validity , which very often is being addressed with regard to three common threats to validity in qualitative studies, namely researcher bias , reactivity and respondent bias (Lincoln and Guba, 1985).

Researcher bias refers to any kind of negative influence of the researcher’s knowledge, or assumptions, of the study, including the influence of his or her assumptions of the design, analysis or, even, sampling strategy. Reactivity , in turn, refers to a possible influence of the researcher himself/herself on the studied situation and people. Respondent bias refers to a situation where respondents do not provide honest responses for any reason, which may include them perceiving a given topic as a threat, or them being willing to ‘please’ the researcher with responses they believe are desirable.

Robson (2002) suggested a number of strategies aimed at addressing these threats to validity, being prolonged involvement , triangulation , peer debriefing , member checking ,  negative case analysis  and keeping an audit trail .

threats to validity.png

So, what exactly are these strategies and how can you apply them in your research?

Prolonged involvement refers to the length of time of the researcher’s involvement in the study, including involvement with the environment and the studied participants. It may be granted, for example, by the duration of the study, or by the researcher belonging to the studied community (e.g. a student investigating other students’ experiences). Being a member of this community, or even being a friend to your participants (see my blog post on the ethics of researching friends ), may be a great advantage and a factor that both increases the level of trust between you, the researcher, and the participants and the possible threats of reactivity and respondent bias. It may, however, pose a threat in the form of researcher bias that stems from your, and the participants’, possible assumptions of similarity and presuppositions about some shared experiences (thus, for example, they will not say something in the interview because they will assume that both of you know it anyway – this way, you may miss some valuable data for your study).

Triangulation may refer to triangulation of data through utilising different instruments of data collection, methodological triangulation through employing mixed methods approach and theory triangulation through comparing different theories and perspectives with your own developing “theory” or through drawing from a number of different fields of study.

Peer debriefing and support is really an element of your student experience at the university throughout the process of the study. Various opportunities to present and discuss your research at its different stages, either at internally organised events at your university (e.g. student presentations, workshops, etc.) or at external conferences (which I strongly suggest that you start attending) will provide you with valuable feedback, criticism and suggestions for improvement. These events are invaluable in helping you to asses the study from a more objective, and critical, perspective and to recognise and address its limitations. This input, thus, from other people helps to reduce the researcher bias.

Member checking , or testing the emerging findings with the research participants, in order to increase the validity of the findings, may take various forms in your study. It may involve, for example, regular contact with the participants throughout the period of the data collection and analysis and verifying certain interpretations and themes resulting from the analysis of the data (Curtin and Fossey, 2007). As a way of controlling the influence of your knowledge and assumptions on the emerging interpretations, if you are not clear about something a participant had said, or written, you may send him/her a request to verify either what he/she meant or the interpretation you made based on that. Secondly, it is common to have a follow-up, “validation interview” that is, in itself, a tool for validating your findings and verifying whether they could be applied to individual participants (Buchbinder, 2011), in order to determine outlying, or negative, cases and to re-evaluate your understanding of a given concept (see further below). Finally, member checking, in its most commonly adopted form, may be carried out by sending the interview transcripts to the participants and asking them to read them and provide any necessary comments or corrections (Carlson, 2010).

Negative case analysis is a process of analysing ‘cases’, or sets of data collected from a single participant, that do not match the patterns emerging from the rest of the data. Whenever an emerging explanation of a given phenomenon you are investigating does nto seem applicable to one, or a small number, of the participants, you should try to carry out a new line of analysis aimed at understanding the source of this discrepancy. Although you may be tempted to ignore these “cases” in fear of having to do extra work, it should become your habit to explore them in detail, as the strategy of negative case analysis, especially when combined with member checking, is a valuable way of reducing researcher bias.

Finally, the notion of keeping an audit trail refers to monitoring and keeping a record of all the research-related activities and data, including the raw interview and journal data, the audio-recordings, the researcher’s diary (see this post about recommended software for researcher’s diary ) and the coding book.

If you adopt the above strategies skilfully, you are likely to minimize threats to validity of your study. Don’t forget to look at the resources in the reference list, if you would like to read more on this topic!

Breakwell, G. M. (2000). Interviewing. In Breakwell, G.M., Hammond, S. & Fife-Shaw, C. (eds.) Research Methods in Psychology. 2nd Ed. London: Sage. Buchbinder, E. (2011). Beyond Checking: Experiences of the Validation Interview. Qualitative Social Work, 10 (1), 106-122. Carlson, J.A. (2010). Avoiding Traps in Member Checking. The Qualitative Report, 15 (5), 1102-1113. Cohen, L., Manion, L., & Morrison, K. (2007). Research Methods in Education. 6th Ed. London: Routledge. Curtin, M., & Fossey, E. (2007). Appraising the trustworthiness of qualitative studies: Guidelines for occupational therapists. Australian Occupational Therapy Journal, 54, 88-94. Lincoln, Y. S. & Guba, E. G. (1985). Naturalistic Inquiry. Newbury Park, CA: SAGE. Robson, C. (2002). Real world research: a resource for social scientists and practitioner-researchers. Oxford, UK: Blackwell Publishers.

Silverman, D. (1993) Interpreting Qualitative Data. London: Sage.

Jarek Kriukow

There is an argument for using your identity and biases to enrich the research (see my recent blog… researcheridentity.wordpress.com) providing that the researcher seeks to fully comprehend their place in the research and is fully open, honest and clear about that in the write up. I have come to see reliability and validity more as a defence of is the research rigorous, thorough and careful therefore is it morally, ethically and accurately defensible?

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Hi Nathan, thank you for your comment. I agree that being explicit about your own status and everything that you bring into the study is important – it’s a very similar issue (although seemingly it’s a different topic) to what I discussed in the blog post about grounded theory where I talked about being explicit about the influence of our previous knowledge on the data. I have also experienced this dilemma of “what to do with” my status as simultaneously a “researcher” an “insider” a “friend” and a “fellow Polish migrant” when conducting my PhD study of Polish migrants’ English Language Identity, and came to similar conclusions as the ones you reach in your article – to acknowledge these “multiple identities” and make the best of them.

I have read your blog article and really liked it – would you mind if I shared it on my Facebook page, and linked to it from my blog section on this page?

Please do share my blog by all means; I’d be delighted. Are you on twitter? I’m @Nathan_AHT_EDD I strongly believe that we cannot escape our past, including our multiple/present habitus and identities when it comes to qualitative educational research. It is therefore, arguably, logical to ethically and sensibly embrace it/them to enrich the data. Identities cannot be taken on and off like a coat, they are, “lived as deeply committed personal projects” (Clegg, 2008: p.336) and so if we embrace them we bring a unique insight into the process and have a genuine investment to make the research meaningful and worthy of notice.

Hi Nathan, I don’t have twitter… I know – somehow I still haven’t had time to get to grips with it. I do have Facebook, feel free to find me there. I also started to follow your blog so that I am notified about your content. I agree with what you said here and in your posts, and I like the topic of your blog. This is definitely something that we should pay more attention to when doing research. It would be interesting to talk some time and exchange opinions, as our research interests seem very closely related. Have a good day !

Issues of validity and reliability in qualitative research

Affiliations.

  • 1 School of Nursing and Midwifery, Queens's University Belfast, Belfast, UK.
  • 2 School of Human and Health Sciences, University of Huddersfield, Huddersfield, UK.
  • PMID: 25653237
  • DOI: 10.1136/eb-2015-102054
  • Qualitative Research*
  • Reproducibility of Results*
  • Research Design / standards

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CRO Guide   >  Chapter 3.1

Qualitative Research: Definition, Methodology, Limitation & Examples

Qualitative research is a method focused on understanding human behavior and experiences through non-numerical data. Examples of qualitative research include:

  • One-on-one interviews,
  • Focus groups, Ethnographic research,
  • Case studies,
  • Record keeping,
  • Qualitative observations

In this article, we’ll provide tips and tricks on how to use qualitative research to better understand your audience through real world examples and improve your ROI. We’ll also learn the difference between qualitative and quantitative data.

gathering data

Table of Contents

Marketers often seek to understand their customers deeply. Qualitative research methods such as face-to-face interviews, focus groups, and qualitative observations can provide valuable insights into your products, your market, and your customers’ opinions and motivations. Understanding these nuances can significantly enhance marketing strategies and overall customer satisfaction.

What is Qualitative Research

Qualitative research is a market research method that focuses on obtaining data through open-ended and conversational communication. This method focuses on the “why” rather than the “what” people think about you. Thus, qualitative research seeks to uncover the underlying motivations, attitudes, and beliefs that drive people’s actions. 

Let’s say you have an online shop catering to a general audience. You do a demographic analysis and you find out that most of your customers are male. Naturally, you will want to find out why women are not buying from you. And that’s what qualitative research will help you find out.

In the case of your online shop, qualitative research would involve reaching out to female non-customers through methods such as in-depth interviews or focus groups. These interactions provide a platform for women to express their thoughts, feelings, and concerns regarding your products or brand. Through qualitative analysis, you can uncover valuable insights into factors such as product preferences, user experience, brand perception, and barriers to purchase.

Types of Qualitative Research Methods

Qualitative research methods are designed in a manner that helps reveal the behavior and perception of a target audience regarding a particular topic.

The most frequently used qualitative analysis methods are one-on-one interviews, focus groups, ethnographic research, case study research, record keeping, and qualitative observation.

1. One-on-one interviews

Conducting one-on-one interviews is one of the most common qualitative research methods. One of the advantages of this method is that it provides a great opportunity to gather precise data about what people think and their motivations.

Spending time talking to customers not only helps marketers understand who their clients are, but also helps with customer care: clients love hearing from brands. This strengthens the relationship between a brand and its clients and paves the way for customer testimonials.

  • A company might conduct interviews to understand why a product failed to meet sales expectations.
  • A researcher might use interviews to gather personal stories about experiences with healthcare.

These interviews can be performed face-to-face or on the phone and usually last between half an hour to over two hours. 

When a one-on-one interview is conducted face-to-face, it also gives the marketer the opportunity to read the body language of the respondent and match the responses.

2. Focus groups

Focus groups gather a small number of people to discuss and provide feedback on a particular subject. The ideal size of a focus group is usually between five and eight participants. The size of focus groups should reflect the participants’ familiarity with the topic. For less important topics or when participants have little experience, a group of 10 can be effective. For more critical topics or when participants are more knowledgeable, a smaller group of five to six is preferable for deeper discussions.

The main goal of a focus group is to find answers to the “why”, “what”, and “how” questions. This method is highly effective in exploring people’s feelings and ideas in a social setting, where group dynamics can bring out insights that might not emerge in one-on-one situations.

  • A focus group could be used to test reactions to a new product concept.
  • Marketers might use focus groups to see how different demographic groups react to an advertising campaign.

One advantage that focus groups have is that the marketer doesn’t necessarily have to interact with the group in person. Nowadays focus groups can be sent as online qualitative surveys on various devices.

Focus groups are an expensive option compared to the other qualitative research methods, which is why they are typically used to explain complex processes.

3. Ethnographic research

Ethnographic research is the most in-depth observational method that studies individuals in their naturally occurring environment.

This method aims at understanding the cultures, challenges, motivations, and settings that occur.

  • A study of workplace culture within a tech startup.
  • Observational research in a remote village to understand local traditions.

Ethnographic research requires the marketer to adapt to the target audiences’ environments (a different organization, a different city, or even a remote location), which is why geographical constraints can be an issue while collecting data.

This type of research can last from a few days to a few years. It’s challenging and time-consuming and solely depends on the expertise of the marketer to be able to analyze, observe, and infer the data.

4. Case study research

The case study method has grown into a valuable qualitative research method. This type of research method is usually used in education or social sciences. It involves a comprehensive examination of a single instance or event, providing detailed insights into complex issues in real-life contexts.  

  • Analyzing a single school’s innovative teaching method.
  • A detailed study of a patient’s medical treatment over several years.

Case study research may seem difficult to operate, but it’s actually one of the simplest ways of conducting research as it involves a deep dive and thorough understanding of the data collection methods and inferring the data.

5. Record keeping

Record keeping is similar to going to the library: you go over books or any other reference material to collect relevant data. This method uses already existing reliable documents and similar sources of information as a data source.

  • Historical research using old newspapers and letters.
  • A study on policy changes over the years by examining government records.

This method is useful for constructing a historical context around a research topic or verifying other findings with documented evidence.

6. Qualitative observation

Qualitative observation is a method that uses subjective methodologies to gather systematic information or data. This method deals with the five major sensory organs and their functioning, sight, smell, touch, taste, and hearing.

  • Sight : Observing the way customers visually interact with product displays in a store to understand their browsing behaviors and preferences.
  • Smell : Noting reactions of consumers to different scents in a fragrance shop to study the impact of olfactory elements on product preference.
  • Touch : Watching how individuals interact with different materials in a clothing store to assess the importance of texture in fabric selection.
  • Taste : Evaluating reactions of participants in a taste test to identify flavor profiles that appeal to different demographic groups.
  • Hearing : Documenting responses to changes in background music within a retail environment to determine its effect on shopping behavior and mood.

Below we are also providing real-life examples of qualitative research that demonstrate practical applications across various contexts:

Qualitative Research Real World Examples

Let’s explore some examples of how qualitative research can be applied in different contexts.

1. Online grocery shop with a predominantly male audience

Method used: one-on-one interviews.

Let’s go back to one of the previous examples. You have an online grocery shop. By nature, it addresses a general audience, but after you do a demographic analysis you find out that most of your customers are male.

One good method to determine why women are not buying from you is to hold one-on-one interviews with potential customers in the category.

Interviewing a sample of potential female customers should reveal why they don’t find your store appealing. The reasons could range from not stocking enough products for women to perhaps the store’s emphasis on heavy-duty tools and automotive products, for example. These insights can guide adjustments in inventory and marketing strategies.

2. Software company launching a new product

Method used: focus groups.

Focus groups are great for establishing product-market fit.

Let’s assume you are a software company that wants to launch a new product and you hold a focus group with 12 people. Although getting their feedback regarding users’ experience with the product is a good thing, this sample is too small to define how the entire market will react to your product.

So what you can do instead is holding multiple focus groups in 20 different geographic regions. Each region should be hosting a group of 12 for each market segment; you can even segment your audience based on age. This would be a better way to establish credibility in the feedback you receive.

3. Alan Pushkin’s “God’s Choice: The Total World of a Fundamentalist Christian School”

Method used: ethnographic research.

Moving from a fictional example to a real-life one, let’s analyze Alan Peshkin’s 1986 book “God’s Choice: The Total World of a Fundamentalist Christian School”.

Peshkin studied the culture of Bethany Baptist Academy by interviewing the students, parents, teachers, and members of the community alike, and spending eighteen months observing them to provide a comprehensive and in-depth analysis of Christian schooling as an alternative to public education.

The study highlights the school’s unified purpose, rigorous academic environment, and strong community support while also pointing out its lack of cultural diversity and openness to differing viewpoints. These insights are crucial for understanding how such educational settings operate and what they offer to students.

Even after discovering all this, Peshkin still presented the school in a positive light and stated that public schools have much to learn from such schools.

Peshkin’s in-depth research represents a qualitative study that uses observations and unstructured interviews, without any assumptions or hypotheses. He utilizes descriptive or non-quantifiable data on Bethany Baptist Academy specifically, without attempting to generalize the findings to other Christian schools.

4. Understanding buyers’ trends

Method used: record keeping.

Another way marketers can use quality research is to understand buyers’ trends. To do this, marketers need to look at historical data for both their company and their industry and identify where buyers are purchasing items in higher volumes.

For example, electronics distributors know that the holiday season is a peak market for sales while life insurance agents find that spring and summer wedding months are good seasons for targeting new clients.

5. Determining products/services missing from the market

Conducting your own research isn’t always necessary. If there are significant breakthroughs in your industry, you can use industry data and adapt it to your marketing needs.

The influx of hacking and hijacking of cloud-based information has made Internet security a topic of many industry reports lately. A software company could use these reports to better understand the problems its clients are facing.

As a result, the company can provide solutions prospects already know they need.

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Qualitative Research Approaches

Once the marketer has decided that their research questions will provide data that is qualitative in nature, the next step is to choose the appropriate qualitative approach.

The approach chosen will take into account the purpose of the research, the role of the researcher, the data collected, the method of data analysis , and how the results will be presented. The most common approaches include:

  • Narrative : This method focuses on individual life stories to understand personal experiences and journeys. It examines how people structure their stories and the themes within them to explore human existence. For example, a narrative study might look at cancer survivors to understand their resilience and coping strategies.
  • Phenomenology : attempts to understand or explain life experiences or phenomena; It aims to reveal the depth of human consciousness and perception, such as by studying the daily lives of those with chronic illnesses.
  • Grounded theory : investigates the process, action, or interaction with the goal of developing a theory “grounded” in observations and empirical data. 
  • Ethnography : describes and interprets an ethnic, cultural, or social group;
  • Case study : examines episodic events in a definable framework, develops in-depth analyses of single or multiple cases, and generally explains “how”. An example might be studying a community health program to evaluate its success and impact.

How to Analyze Qualitative Data

Analyzing qualitative data involves interpreting non-numerical data to uncover patterns, themes, and deeper insights. This process is typically more subjective and requires a systematic approach to ensure reliability and validity. 

1. Data Collection

Ensure that your data collection methods (e.g., interviews, focus groups, observations) are well-documented and comprehensive. This step is crucial because the quality and depth of the data collected will significantly influence the analysis.

2. Data Preparation

Once collected, the data needs to be organized. Transcribe audio and video recordings, and gather all notes and documents. Ensure that all data is anonymized to protect participant confidentiality where necessary.

3. Familiarization

Immerse yourself in the data by reading through the materials multiple times. This helps you get a general sense of the information and begin identifying patterns or recurring themes.

Develop a coding system to tag data with labels that summarize and account for each piece of information. Codes can be words, phrases, or acronyms that represent how these segments relate to your research questions.

  • Descriptive Coding : Summarize the primary topic of the data.
  • In Vivo Coding : Use language and terms used by the participants themselves.
  • Process Coding : Use gerunds (“-ing” words) to label the processes at play.
  • Emotion Coding : Identify and record the emotions conveyed or experienced.

5. Thematic Development

Group codes into themes that represent larger patterns in the data. These themes should relate directly to the research questions and form a coherent narrative about the findings.

6. Interpreting the Data

Interpret the data by constructing a logical narrative. This involves piecing together the themes to explain larger insights about the data. Link the results back to your research objectives and existing literature to bolster your interpretations.

7. Validation

Check the reliability and validity of your findings by reviewing if the interpretations are supported by the data. This may involve revisiting the data multiple times or discussing the findings with colleagues or participants for validation.

8. Reporting

Finally, present the findings in a clear and organized manner. Use direct quotes and detailed descriptions to illustrate the themes and insights. The report should communicate the narrative you’ve built from your data, clearly linking your findings to your research questions.

Limitations of qualitative research

The disadvantages of qualitative research are quite unique. The techniques of the data collector and their own unique observations can alter the information in subtle ways. That being said, these are the qualitative research’s limitations:

1. It’s a time-consuming process

The main drawback of qualitative study is that the process is time-consuming. Another problem is that the interpretations are limited. Personal experience and knowledge influence observations and conclusions.

Thus, qualitative research might take several weeks or months. Also, since this process delves into personal interaction for data collection, discussions often tend to deviate from the main issue to be studied.

2. You can’t verify the results of qualitative research

Because qualitative research is open-ended, participants have more control over the content of the data collected. So the marketer is not able to verify the results objectively against the scenarios stated by the respondents. For example, in a focus group discussing a new product, participants might express their feelings about the design and functionality. However, these opinions are influenced by individual tastes and experiences, making it difficult to ascertain a universally applicable conclusion from these discussions.

3. It’s a labor-intensive approach

Qualitative research requires a labor-intensive analysis process such as categorization, recording, etc. Similarly, qualitative research requires well-experienced marketers to obtain the needed data from a group of respondents.

4. It’s difficult to investigate causality

Qualitative research requires thoughtful planning to ensure the obtained results are accurate. There is no way to analyze qualitative data mathematically. This type of research is based more on opinion and judgment rather than results. Because all qualitative studies are unique they are difficult to replicate.

5. Qualitative research is not statistically representative

Because qualitative research is a perspective-based method of research, the responses given are not measured.

Comparisons can be made and this can lead toward duplication, but for the most part, quantitative data is required for circumstances that need statistical representation and that is not part of the qualitative research process.

While doing a qualitative study, it’s important to cross-reference the data obtained with the quantitative data. By continuously surveying prospects and customers marketers can build a stronger database of useful information.

Quantitative vs. Qualitative Research

Qualitative and quantitative research side by side in a table

Image source

Quantitative and qualitative research are two distinct methodologies used in the field of market research, each offering unique insights and approaches to understanding consumer behavior and preferences.

As we already defined, qualitative analysis seeks to explore the deeper meanings, perceptions, and motivations behind human behavior through non-numerical data. On the other hand, quantitative research focuses on collecting and analyzing numerical data to identify patterns, trends, and statistical relationships.  

Let’s explore their key differences: 

Nature of Data:

  • Quantitative research : Involves numerical data that can be measured and analyzed statistically.
  • Qualitative research : Focuses on non-numerical data, such as words, images, and observations, to capture subjective experiences and meanings.

Research Questions:

  • Quantitative research : Typically addresses questions related to “how many,” “how much,” or “to what extent,” aiming to quantify relationships and patterns.
  • Qualitative research: Explores questions related to “why” and “how,” aiming to understand the underlying motivations, beliefs, and perceptions of individuals.

Data Collection Methods:

  • Quantitative research : Relies on structured surveys, experiments, or observations with predefined variables and measures.
  • Qualitative research : Utilizes open-ended interviews, focus groups, participant observations, and textual analysis to gather rich, contextually nuanced data.

Analysis Techniques:

  • Quantitative research: Involves statistical analysis to identify correlations, associations, or differences between variables.
  • Qualitative research: Employs thematic analysis, coding, and interpretation to uncover patterns, themes, and insights within qualitative data.

validity and reliability in qualitative and quantitative research

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  • Last modified: January 3, 2023
  • Conversion Rate Optimization , User Research

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COMMENTS

  1. Validity, reliability, and generalizability in qualitative research

    In quantitative research, reliability refers to exact replicability of the processes and the results. In qualitative research with diverse paradigms, such definition of reliability is challenging and epistemologically counter-intuitive. ... From a realism standpoint, Porter then proposes multiple and open approaches for validity in qualitative ...

  2. Reliability vs. Validity in Research

    Reliability is about the consistency of a measure, and validity is about the accuracy of a measure.opt. It's important to consider reliability and validity when you are creating your research design, planning your methods, and writing up your results, especially in quantitative research. Failing to do so can lead to several types of research ...

  3. (PDF) Validity and Reliability in Quantitative Research

    Reliability, Quantitative Res earch. JEL Codes: C12, C15, C42. Validity and eliability of the scales used in research are essential. that enable the re search to yield beneficialresults. For this ...

  4. (PDF) Validity and Reliability in Qualitative Research

    Validity and reliability or trustworthiness are fundamental issues in scientific research whether. it is qualitative, quantitative, or mixed research. It is a necessity for researchers to describe ...

  5. Understanding Reliability and Validity in Qualitative Research

    Kirk and Miller (1986) identify three types of reliability referred to in quantitative research, which relate to: (1) the degree to which a measurement, given repeatedly, remains the same (2) the stability of a measurement over time; and (3) the similarity of measurements within. a given time period (pp. 41-42).

  6. Validity and reliability in quantitative studies

    Validity. Validity is defined as the extent to which a concept is accurately measured in a quantitative study. For example, a survey designed to explore depression but which actually measures anxiety would not be considered valid. The second measure of quality in a quantitative study is reliability, or the accuracy of an instrument.In other words, the extent to which a research instrument ...

  7. Issues of validity and reliability in qualitative research

    Although the tests and measures used to establish the validity and reliability of quantitative research cannot be applied to qualitative research, there are ongoing debates about whether terms such as validity, reliability and generalisability are appropriate to evaluate qualitative research.2-4 In the broadest context these terms are applicable, with validity referring to the integrity and ...

  8. Contextualizing reliability and validity in qualitative research

    Rather than prescribing what reliability and/or validity should look like, researchers should attend to the overall trustworthiness of qualitative research by more directly addressing issues associated with reliability and/or validity, as aligned with larger issues of ontological, epistemological, and paradigmatic affiliation.

  9. Rigor or Reliability and Validity in Qualitative Research: Perspectives

    Issues are still raised even now in the 21st century by the persistent concern with achieving rigor in qualitative research. There is also a continuing debate about the analogous terms reliability and validity in naturalistic inquiries as opposed to quantitative investigations. This article presents …

  10. SAGE Research Methods: Find resources to answer your research methods

    Learn how to assess the reliability and validity of qualitative research from Kirk and Miller, experts in the field. A concise and accessible guide for students and researchers.

  11. Understanding validity and reliability from qualitative and

    reliability and validity are tre ated differently. in qualitative and quantitative traditions. While quantitative research emphasizes the. importance of the consistency of research. re sults which ...

  12. Validity in Qualitative Research: A Processual Approach

    Validity in Qualitative Research: A Processual Approach . Abstract . Validity and reliability of research and its results are important elements to provide evidence of the quality of research in the organizational field. However, validity is better evidenced in quantitative studies than in qualitative research studies.

  13. The Significance of Validity and Reliability in Quantitative Research

    Quantitative research is used to investigate and analyze data to draw meaningful conclusions. Validity and reliability are two critical concepts in quantitative analysis that ensure the accuracy and consistency of the research results. Validity refers to the extent to which the research measures what it intends to measure, while reliability ...

  14. Validity, reliability, and generalizability in qualitative research

    Fundamental concepts of validity, reliability, and generalizability as applicable to qualitative research are then addressed with an update on the current views and controversies. Keywords: Controversies; generalizability; primary care research; qualitative research; reliability; validity. In general practice, qualitative research contributes ...

  15. Reliability and validity in research

    Reproducibility of Results. Research Design / standards*. Research Personnel / psychology. This article examines reliability and validity as ways to demonstrate the rigour and trustworthiness of quantitative and qualitative research. The authors discuss the basic principles of reliability and validity for readers who are new to research.

  16. How is reliability and validity realized in qualitative research?

    Reliability in qualitative research refers to the stability of responses to multiple coders of data sets. It can be enhanced by detailed field notes by using recording devices and by transcribing the digital files. However, validity in qualitative research might have different terms than in quantitative research. Lincoln and Guba (1985) used "trustworthiness" of ...

  17. PDF Measurement Validity: A Shared Standard for Qualitative and

    In the process we seek to formulate a methodological standard that can be applied in both qualitative and quantitative research. Measurement validity is specifically concerned with whether operationalization and the scoring of cases adequately reflect the concept the researcher seeks to measure.

  18. Validity and validation in qualitative and quantitative research

    A Handbook of Media and Communication Research. Qualitative and Quantitative Methodologies. London: Routledge. Google Scholar ... [Reliability as a pedagogical problem] (Report No. 9:1995) Oslo: University of Oslo, Institute for Educational Research. ... In S. Kvale (ed.): Issues of Validity in Qualitative Research. Lund: Studentlitteratur ...

  19. A Discussion of the Concepts of Validity and Reliability in Qualitative

    The purpose of this paper is discussing the main issues in conceptualizing reliability and validity between qualitative and quantitative research approaches. The researcher examined the arguments about validity and reliability in inquiry methodology and identified three main debates primarily in qualitative research. The first one was about qualitative inquirers' limited emphasis on the data ...

  20. Understanding validity and reliability from qualitative and

    Educational constructs change over time to reflect developments in research and educational approaches. To illustrate the process, this article aims to examine validity and reliability, which are important concepts to justify research quality. Originally, validity and reliability were applied to quantitative research. However, these criteria can not be equally applied to qualitative research ...

  21. Validity and Reliability in Qualitative research

    In Quantitative research, reliability refers to consistency of certain measurements, and validity - to whether these measurements "measure what they are supposed to measure". Things are slightly different, however, in Qualitative research. Reliability in qualitative studies is mostly a matter of "being thorough, careful and honest in ...

  22. (PDF) Reliability and Validity of Qualitative and Operational Research

    Without this paradigm shift requiring a "redefinition in order to fit the realities of qualitative research" (Strauss and Corbin, 1990, p. 250), the concept of reliability and validity would be ...

  23. Criteria for Assessing and Ensuring the Trustworthiness in Qualitative

    considered the validity and reliability of qualitative research not to suit the naturistic work. ... and internal reliability in quantitative research is only applicable to trustworthiness if the researchers believe in one single reality. The researcher Sandelowski (1986) explains that if the respondents of the study or any individual ...

  24. Issues of validity and reliability in qualitative research

    Issues of validity and reliability in qualitative research. Issues of validity and reliability in qualitative research. Evid Based Nurs. 2015 Apr;18 (2):34-5. doi: 10.1136/eb-2015-102054. Epub 2015 Feb 4.

  25. Transferability and Generalization in Qualitative Research

    Schofield (1990, p. 202) states that qualitative research texts in the 1980s "paid little attention" to the question of generalization. For example, she notes that external validity was minimally addressed in Kirk and Miller's monograph addressing validity in qualitative research and in Berg's methods text. She summarizes that this was ...

  26. Qualitative Research: Definition, Methodology, Limitation, Examples

    Check the reliability and validity of your findings by reviewing if the interpretations are supported by the data. This may involve revisiting the data multiple times or discussing the findings with colleagues or participants for validation. ... Quantitative and qualitative research are two distinct methodologies used in the field of market ...

  27. Is this the first time that you heard about Qualitative and

    Qualitative and quantitative research methods are both familiar to me, as they are fundamental approaches used in various fields. ... Validity and reliability are critical considerations in research design, regardless of the chosen methodology. Qualitative research emphasizes validity through techniques such as triangulation, member checking ...

  28. Short Sea Shipping as a Sustainable Modal Alternative: Qualitative and

    This study investigated the possibility of using short sea shipping (SSS) as a sustainable freight modal alternative by analyzing data collected from shippers in the New York State Capital Region. To this end, qualitative and quantitative approaches were jointly used. The qualitative analysis focused on exploring in-depth interviews with the decision makers regarding the drivers and the ...