Estimation of Sample Size in Biomedical Research: A Quick Guide for Postgraduate Medical Students

  • Ahmad Najmi Assistant Professor, Department of Pharmacology, AIIMS Bhopal
  • S Balakrishnan Professor & Head, Department of Pharmacology, AIIMS Bhopal
  • S. Avik Ray Resident, Department of Pharmacology, AIIMS Bhopal
Keywords: sample size, postgraduate thesis, dissertation, medical student


Calculation of sample size becomes a challenging task for many of the postgraduate medical students. Given the time and resource constraints, it often becomes quite overwhelming for the resident doctors to come up with a feasible sample size obtained scientifically and with a statistical validity, given that for most medical students, the postgraduate thesis work is the stepping stone to the dynamic world of medical research. While some propose very high numbers and end up collecting data from a much smaller sample, thus compromising on the study power, some state too small a sample size to draw any valid conclusion. This article is meant to serve as a quick guide for the postgraduate medical student and budding biomedical researchers to understand ways to calculate sample size.


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How to Cite
Najmi A, Balakrishnan S, Ray SA. Estimation of Sample Size in Biomedical Research: A Quick Guide for Postgraduate Medical Students. Int Arch BioMed Clin Res [Internet]. 2021Oct.9 [cited 2021Oct.23];7(3):PH1-PH3. Available from: