How to calculate sample size and why

Clin Orthop Surg. 2013 Sep;5(3):235-42. doi: 10.4055/cios.2013.5.3.235. Epub 2013 Aug 20.


Why: Calculating the sample size is essential to reduce the cost of a study and to prove the hypothesis effectively.

How: Referring to pilot studies and previous research studies, we can choose a proper hypothesis and simplify the studies by using a website or Microsoft Excel sheet that contains formulas for calculating sample size in the beginning stage of the study.

More: There are numerous formulas for calculating the sample size for complicated statistics and studies, but most studies can use basic calculating methods for sample size calculation.

Keywords: Sample size.

MeSH terms

  • Chi-Square Distribution
  • Research Design*
  • Sample Size*
  • Statistics as Topic / methods*