The Calculators and Utilities provided below may help you in developing your study

Sample Size -- Means
Comparing means (t-test)
Sample Size -- Proportions
Comparing proportions (chi-square test)
Sample Size -- Confidence Interval For the Mean of a Continuous Measurement
Estimating a mean with a confidence interval of a particular width
Sample Size -- Confidence Interval For a Proportion
Estimating a proportion with a confidence interval of a particular width
Sample Size -- Survival Analysis
Estimating Sample Sizes for Time-to-Event Analysis
Confidence Interval -- Likelihood Ratio
Confidence Interval for a Likelihood Ratio
Posterior Probability of Disease Calculator
Determine the Posterior Probability of Disease Given a Particular Test Result
BMI Calculator - Adult
Simple BMI Calculator based on weight and height
BMI Percentile Calculator - Pediatric
Pediatric BMI Percentile Calculator based on a child's age, gender, weight and height.
Provides BMI and Percentile values
Blood Pressure Calculator - Pediatric
Pediatric Blood Pressure Calculator based on age and height. Provides Percentiles for SBP and DBP
Apache III Score Calculator (Beta)
Provides a Apache III Score for a critical patient.
If you have comments, corrections or ideas about new tools you would like to see, please send email to and let us know.