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. 2013 Winter;6(1):14-7.

Sample size calculation in medical studies

Mohamad Amin Pourhoseingholi  1 , Mohsen Vahedi  2 , Mitra Rahimzadeh  3
Affiliations

Sample size calculation in medical studies

Mohamad Amin Pourhoseingholi et al. Gastroenterol Hepatol Bed Bench. 2013 Winter.

Abstract

Optimum sample size is an essential component of any research. The main purpose of the sample size calculation is to determine the number of samples needed to detect significant changes in clinical parameters, treatment effects or associations after data gathering. It is not uncommon for studies to be underpowered and thereby fail to detect the existing treatment effects due to inadequate sample size. In this paper, we explain briefly the basic principles of sample size calculations in medical studies.

Keywords: Medical studies; Sample size.

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