Determining Sample Size in Qualitative Research: From Data Saturation to Theoretical Saturation
Keywords:
Data saturation, Theoretical saturation, Sample size, Information power, Qualitative research methodologyAbstract
Determining sample size in qualitative research is a critical methodological issue as it directly affects data depth, finding reliability, and academic credibility. This article explains the distinction between data saturation, which emphasizes content completeness, and theoretical saturation, which emphasizes sufficiency in explanation and theory development. It presents the concept of information power and a five-step operational framework, synthesized from contemporary literature by the authors, for systematic and accountable sample size planning and decision-making. The article identifies common methodological errors and proposes evidence-based solutions for contemporary practice. The goal is to elevate sample size determination from descriptive adequacy to explanatory adequacy with theoretical depth.
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