Sample size requirements for sensitivity and specificity analyses

Calculating the sample size is a crucial step in the design of a research study. The method to calculate a sample size varies by the statistical methodologies and design of a study and hence, it may become slightly tricky and challenging.

An article published in the Journal of Clinical & Diagnostic Research, Requirements for Minimum Sample Size for Sensitivity and Specificity Analysis (Bujang & Adnan, 2016), offers sample size calculations for a specific type of research study, i.e., a screening or diagnostic study. In such studies, the researcher plans to develop a specific tool/instrument to be used as a diagnostic tool or determine if a specific tool/instrument can be used as a screening tool. Hence, sensitivity and specificity analyses are commonly used and based on your research objectives, you may want a high sensitivity, high specificity, or both. This article offers a guide to sample size calculations for sensitivity and specificity analyses for screening and diagnostic studies considering the prevalence of disease in these calculations and by fixing the values of power and type 1 error. The tables in this article clearly show how the sample size for these types of studies will change as the prevalence of the disease increases or decreases. We hope you find this resource helpful.

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Reference: Bujang, M. A., & Adnan, T. H. (2016). Requirements for Minimum Sample Size for Sensitivity and Specificity Analysis. Journal of clinical and diagnostic research : JCDR, 10(10), YE01–YE06. https://doi.org/10.7860/JCDR/2016/18129.8744