Use these calculators for studies examining means or proportions, studies with clustered data, survival analysis, and more.
What the video offers
This site includes calculators for the necessary sample size to detect a user-defined effect size or the minimum detectable effect size for a user-defined sample size. The types of studies and analyses accommodated by these calculators are broad and include:
- One group, two independent groups, and paired group designs
- Tests for means, proportions, and correlation
- Clustered data
- Confidence intervals
- Survival analysis
- Likelihood ratio (diagnostic test accuracy)
- Posterior probability of disease
- Pediatric growth
Each calculator includes helpful descriptions of the required inputs. They also include descriptions of the method used for sample size/effect size calculations along with relevant formulas and references. This website also has two tabs at the top: “About Calculating Sample Size” and “Glossary of Terms” which offer explanations of sample size vocabulary as well as study design considerations.
Helpful hint: Don’t miss the “About Calculating Sample Size” and “Glossary of Terms” tabs for more information about sample size calculations.
Who it's for
- Clinical investigators
Who created it
This site is run by the University of California San Francisco Clinical and Translational Science Institute.