Intended for healthcare professionals

Practice Qualitative Research

Critically appraising qualitative research

BMJ 2008; 337 doi: (Published 07 August 2008) Cite this as: BMJ 2008;337:a1035

Re: Critically appraising qualitative research

This letter is inspired by the article 'Critically appraising qualitative research', by Kuper, Lingard, and Levinson (2008). I agree with the authors about the six key questions they mention. However, in my opinion, the list misses two more important questions. I discuss them below.

Key question 1. Was the research method and techniques used in the study relevant for the research question?

The first question Kuper and colleagues suggest to the readers of qualitative research is “Was the sample used in the study relevant for the research question?” However, in my opinion, this relevant question should be preceded by another query: “Was the research method and techniques used in the study relevant for the research question?” For instance, in the paper by Soklaridis (2009), the authors discuss why in-depth interviews were conducted:

“It was possible to gain an understanding of how the stakeholders at the clinic interact with each other, how they interpret those interactions, and how these meanings are informed by the wider socio-political context in which IHC (Integrative Health Care) takes place.”

When the readers look for this clear exemplification of reasons behind the choice of research method and instrument, they will be able to ascertain how right the methods and operational measures are for studying the involved concepts. This in turn will also help them understand the study’s trustworthiness potential, in particular, its credibility.

Key question 2. Can I make sure the results presented by the researchers are credible?

Another question which Kuper et al. (2008) put forth to readers is regarding the transferability of the study’s findings. (‘Can I transfer the results of the study to my own setting’?) Indeed, transferability is an important parameter for ensuring trustworthiness. However, like its positivistic counterpart ‘external validity’, it is given much more importance than other important parameters like ‘credibility’ (‘internal validity’). Prior researchers have made calls for clarifying these misconceptions (Tsang and Williams, 2012) in the debate surrounding transferability/external validity as seemingly the only criterion worth worrying about in qualitative research. So I suggest to the readers to ponder on the question ‘Can I make sure the results are credible?’ also while reading a qualitative study.

But then, what are theways to ensure a study has credibility? Along with checking for any mentioning of the rationale for research method selection (which we discussed under Key question 1), researchers can ensure credibility by following the chain of evidence given in the report. This would help one in reconstructing how the research developed from initial research questions to final conclusions (Kaufmann and Denk, 2011; Yin, 1994).


Kaufmann, L., & Denk, N. (2011). How to demonstrate rigor when presenting grounded theory research in the supply chain management literature. Journal of Supply Chain Management, 47(4), 64-72.

Kuper, A., Lingard, L., & Levinson, W. (2008). Critically appraising qualitative research. Bmj, 337(aug07_3), a1035-a1035.

Soklaridis, S. (2009). The process of conducting qualitative grounded theory research for a doctoral thesis: Experiences and reflections. The qualitative report, 14(4), 719.

Tsang, E. K., & Williams, J. N. (2012). Generalization and induction : Misconceptions, clarifications, and a classification of induction. MIS Quarterly, 36(3), 729-748.

Yin, R. K. (1994). Case study research : Design and methods. Thousand Oaks: Sage.

Competing interests: No competing interests

20 July 2017
Lakshmi Balachandran Nair
Assistant Professor
Utrecht University
Sjoerd Groenmangebouw, Padualaan 14, Utrecht, The Netherlands, 3584 CH