Developed by the Centers for Disease Control and Prevention (CDC), Atlanta, Georgia USA, Epi Info has been in existence for over 20 years and is currently available for Microsoft Windows. The program allows for data entry and analysis. Within the analysis module, analytic routines include t-tests, ANOVA, nonparametric statistics, cross tabulations and stratification with estimates of odds ratios, risk ratios, and risk differences, logistic regression (conditional and unconditional), survival analysis (Kaplan Meier and Cox proportional hazard), and analysis of complex survey data.
Epi Info is free and can be downloaded at www.cdc.gov/epiinfo. There is limited support available for users.