MedCalc is a complete statistical program for Windows designed to closely match the requirements of biomedical researchers. It is fast, user-friendly and reliable. MedCalc is the most user-friendly software for Receiver Operating Characteristic curve (ROC curves) analysis. The MedCalc ROC module includes comparison of up to 6 ROC curves. The software also includes Bland & Altman plot, Passing and Bablok and Deming regression for method comparison studies.