Qualitative Research Designs, Sample Size and Saturation: Is Enough Always Enough?

Abstract

Qualitative research is currently growing in acceptance, especially within the health research scope. Notwithstanding this positive trend, issues about the adequacy of sample size have been a contention among qualitative and quantitative-based researchers. Our paper seeks to address some of the issues facing popular qualitative designs in human research with this backdrop. Our article explains the five key qualitative designs (case study, narrative inquiry, ethnography, phenomenology, and grounded theory). Based on the existing studies, we reported their respective sample size ranges that supported their data adequacy points. Our paper posits that sample size concerns for qualitative designs revolve around their extensiveness and appropriateness. Therefore, qualitative researchers' judgement for data adequacy for a particular method should not only rely on data saturation or a rule-of-thumb. Instead, they should also be guided by their research goals, sampling approach, and research participants. Furthermore, we recommend that qualitative researchers always verify the quality of data saturation by conducting additional interviews and be more open in reporting their selected methodologies.