The types of calculations currently performed by OpenEpi include: • Various
confidence intervals for
proportions, rates,
standardized mortality ratio,
mean,
median,
percentiles • 2x2 crude and stratified tables for count and rate data • Matched
case-control analysis • Test for trend with
count data • Independent t-test and one-way
ANOVA • Diagnostic and
screening test analyses with
receiver operating characteristic (ROC) curves •
Sample size for proportions,
cross-sectional surveys, unmatched
case-control,
cohort,
randomized controlled trials, and comparison of two means • Power calculations for proportions (unmatched
case-control,
cross-sectional,
cohort,
randomized controlled trials) and for the comparison of two means • Random number generator For epidemiologists and other health researchers, OpenEpi performs a number of calculations based on tables not found in most epidemiologic and statistical packages. For example, for a single 2x2 table, in addition to the results presented in other programs, OpenEpi provides estimates for: • Etiologic or prevented fraction in the population and in exposed with confidence intervals, based on risk, odds, or rate data • The cross-product and MLE
odds ratio estimate • Mid-p exact p-values and confidence limits for the
odds ratio • Calculations of rate ratios and rate differences with
confidence intervals and statistical tests. For
stratified 2x2 tables with count data, OpenEpi provides: •
Mantel-Haenszel (MH) and precision-based estimates of the risk ratio and odds ratio • Precision-based adjusted risk difference • Tests for interaction for the
risk ratio,
odds ratio, and risk difference • Four different confidence limit methods for the odds ratio. Similar to Epi Info, in a stratified analysis, both crude and adjusted estimates are provided so that the assessment of
confounding can be made. With rate data, OpenEpi provides adjusted rate ratio's and rate differences, and tests for
interaction. Finally, with count data, OpenEpi also performs a test for trend, for both crude data and stratified data. In addition to being used to analyze data by health researchers, OpenEpi has been used as a training tool for teaching epidemiology to students at:
Emory University,
University of Massachusetts,
University of Michigan,
University of Minnesota,
Morehouse College,
Columbia University,
University of Wisconsin,
San Jose State University,
University of Medicine and Dentistry of New Jersey,
University of Washington, and elsewhere. This includes campus-based and distance learning courses. Because OpenEpi is easy to use, requires no programming experience, and can be run on the internet, students can use the program and focus on the interpretation of results. Users can run the program in English, French, Spanish, Portuguese or Italian. Comments and suggestions for improvements are welcomed and the developers respond to user queries. The developers encourage others to develop modules that could be added to OpenEpi and provide a developer's tool at the website. Planned future development include improvements to existing modules, development of new modules, translation into other languages, and add the ability to cut and paste data and/or read data files. ==See also==