Sampling in Qualitative Research: Insights from a Systematic Overview of the Methods Literature

Abstract

The methods literature regarding sampling in qualitative research is characterized by important inconsistencies and ambiguities, which can be problematic for students and researchers seeking a clear and coherent understanding. Here, I will present insights about sampling in qualitative research derived from a systematic methods overview conducted of the literature from three research traditions: grounded theory, phenomenology, and case study. In this review, recently published in TQR, we identified and selected influential methods literature from each tradition using a purposeful and transparent procedure, abstracted textual data using structured abstraction forms, and used a multistep approach for deriving conclusions from the data. The findings are organized into eight topic sections corresponding to the major domains of sampling identified in the review process: definitions of sampling, usage of the term sampling strategy, purposeful sampling, theoretical sampling, sampling units, saturation, sample size, and the timing of sampling decisions. I will summarize how each topic is characterized in the literature selected for review, presenting our comparative analysis of important differences among research traditions, and our analytic conclusions for each topic