Sample size calculation

Introduction Sample size is defined as the number of experimental units needed for a study. The required sample size of a study is determined by the distribution and type of data. The determination of sample size aids a researcher in estimating project costs, timelines, and viability. In this review, we outline the fundamental ideas underlying sample size calculations [Table 1]. The need for accurate sample size estimation is to determine the minimum number of participants required to find a clinically significant outcome. With a sample size that is too small, a major existing influence cannot be identifiable, and if samples are too large might be a time, resource, and cost drain.[5,6] Steps to calculate sample sizeTable 1:: Algorithmic approach to calculating sample sizeComponents of sample size estimationTable 2:: Components of sample size estimationFormula for sample size estimationTable 3:: References for formula derivation and applicationSome software that can be used for the calculation of sample sizeTable 4:: URLs of statistical software for sample size estimationFinancial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.