| # About OpenEpi

# A Collaborative, Open-Source Project in Epidemiologic Computing

# The OpenEpi Collection of Epidemiologic Calculators

### Version 2.3 ----- May 2009

### See Main Menu for a Suggested Citation

### and

### Individual Modules for Authors and Addresses

#### OpenEpi is an Open Source effort to replace and extend the EpiTable and Statcalc programs in Epi Info with web-compatible programs and links in JavaScript. Although OpenEpi is not a direct product of the Centers for Disease Control and Prevention(CDC), OpenEpi and Epi Info development and testing have been supported in part by a grant from the Bill and Melinda Gates Foundation to Emory University.

##

# Background

## • Commercial software does not always meet the needs of epidemiologists

## • Hundreds of statistical calculators are available, e.g., Statcalc, PEPI, spreadsheet-based, web-based, etc.

## • There is wide variation in usability, layout, documentation, breadth of coverage, accuracy, and access to source code

##

# Goals of OpenEpi

## • Provide up-to-date, documented, tested programs using a common interface

## • Run programs across the web or locally

## • Platform independence

## • Open Source approach

## • Foster interaction among epidemiologists and others in development

##

# How does OpenEpi achieve these goals?

## • Use of JavaScript and HTML

### – Platform independent (Win, Mac, Unix)

### – Included with browsers (Explorer, Netscape, etc.)

### – Interpretive (source code available)

### – Make programs available from a server or allow user to download and run locally

## • Common Interface

### – Standard data entry screens

### – Standard output

### – Standard graphics

###

# Status of OpenEpi …

## • Analytic routines (for users)

### – CI for a single proportion or rate, median percentile

– t-test and ANOVA

### – 2x2 table (counts or person-time rates)

### – RxC table

### – Pair-matched analysis

### – Sample size calculators for proportions, unmatched case-control and cohort studies, and mean difference

– Power calculations for cohort, cross-sectional, and unmatched case-control studies, clinical trials, and mean difference

### – Random number generator

### – Dose Response (chi square for trend)

### – Diagnostic method evaluation

– Options to set table orientation, confidence level, and (if available) language

– Ability to download the entire package and run it from a hard disk or from a CDROM

## • Tool box for developers

## • Simple methods for translation into non English languages

##

# Features …

## • Stratified tables

## • Screening tests

## • Saving result files (MS Windows only for now)

## • Loading demo data from result file

## • File naming convention and directory structure

## • Robust data entry (no instructions needed)

## • Automatic column and row totals

## • 'Check Code' in JavaScript

## • HTML output

##

# Collaboration

## • We would like your input:

### – What types of analyses?

### – Did you find any problems or errors?

### – Would you assist in testing programs?

### – Would you like to develop programs?

### – Which links should we have?

### – Please email us at the addresses on the main menu

##