Sample Size Determination

This is a free website you can use to determine sample size for your research project. No need to register.

Estimation of a parameter with specified precision	Estimation of a mean with specified precision	Estimation of a proportion / prevalence with specified precision
Estimation of a effect size in Case Control or Cohort study with specified precision	Estimation of Odds Ratio in Case Control Study with specified precision	Estimation of Relative Risk in Cohort Study with specified precision
Estimation of Kappa statistics with specified precision	Estimation of Pearson's Correlation Coefficient with specified precision
Hypohesis Testing - One Sample	Significant difference between sample mean and hypothetical / known value	Significant difference between sample proportion and hypothetical / known value
Hypohesis Testing - Two Samples	Significant difference between two sample means	Significant difference between two sample Proportions
Clinical Trial - Superiority Design	Outcome variable: Ratio	Clinical Trial-Superiority design (Outcome variable: Nominal)
Clinical Trial - Non-Inferiority Design	Outcome variable:Ratio	Outcome variable: Nominal
Clinical Trial - Equivalence Design	Outcome variable:Ratio	Outcome variable: Nominal
Case-Control or Cohort Studies	Odds Ratio is Significantly different than 1 (Significant OR)	Relative Risk is Significantly different than 1 (Significant RR)