I return to the conduct of qualitative research. Such research has two main differences from the more well-understood quantitative research: (1) it focuses on social and interpreted, rather than quantifiable, phenomenon, and (2) it aims to discover, describe, and understand, rather than to test and evaluate. It looks at very different questions than does quantitative research. Here is one example: consider a project that wishes to examine changes in pain intensity among a group of patients with low back pain. We can, using quantitative methods, collect baseline pain readings using an instrument such as a Numerical Rating Scale (pain rated on a scale of 0-10, with 0 being no pain and 10 be the worst pain imaginable. We can then collect follow-up ratings 2 weeks after treatment. Each person provides their own self-rated pain measures. Patient #1 might have an initial score of 8 and a follow-up score of 4; patient #2 might report the exact same measures. But, does this mean that their experience and perceptions regarding the pain they experience is exactly the same? We cannot know using quantitative methods. Instead, we might conduct a corollary project in which we interview a select group of patients, so that we can have a better sense and understanding of their lived experience with pain. We would have descriptive information to analyze: words, and text. As a result those who conduct qualitative research rarely discuss validity; instead, they discuss credibility.
There are a series of questions one can use to read and interpret papers presenting qualitative research. According to the Users’ Guides to the Medical Literature (1), questions to ask include:
Is qualitative research relevant? Is my question about social, rather than biomedical, phenomenon? Do I want theoretical or conceptual understanding of the problem?
Are the results credible? Was the choice of participants explicit and comprehensive? Was ethics approval received? Was data collection comprehensive and detailed?
What are the results?
How can I apply the results to patient care? Does the study offer helpful theory? Does it help me understand the context of my practice? Does it help me understand social interactions in clinical care?
These are all good questions through which to view the methods and results of a qualitative study.
1. Guyatt G, Rennie D, Meade MO, Cook DJ. Users’ guides to the medical literature, 2nd edition. New York City, NY; McGraw Hill, 2008:341-360