Epi Info is a public domain suite of interoperable software tools for Microsoft Windows, designed for the global community of public health practitioners and researchers. It provides easy data entry form and database construction, a customized data entry experience, and data analyses with epidemiologic statistics, maps, and graphs for public health professionals who may lack an informational technology background.
Epi Info is used for outbreak investigation, for developing small to mid-sized disease surveillance systems, as analysis, visualization and reporting (AVR) components of larger systems, and in the continuing education in the science of epidemiology and public health analytic methods at schools of public health around the world.
Originally Epi Info was developed for the Centers for Disease Control and Prevention (CDC) own investigators. It was meant to provide tools for Epidemiologist and field investigators including, sample size calculators, 2X2 table calculators and questionnaires for case-control studies. Since 1998, there have been approximately 2,000,000 successful downloads of Epi Info from the CDC website in 180 countries. For many countries Epi Info provides the core surveillance system for imminizable disease for 27 African countries and covers over 25% of surveillance monitoring for Acute Flaccid Paralysis in India.
- Free for all users.
- Easy to select subsets of data for analysis, without having to delete records or make multiple copies of datasets.
- Keeps a saveable record of the analysis steps you have performed.
- Automatically includes all VALID data points in calculations/tests.
- Performs both descriptive statistics and a lot of basic to intermediate analysis (e.g., comparisonof means, proportions; many regression methods)
- Can be used for data entry - uses an Access-like data storage system.
- Runs under Windows only.
- Can be difficult to learn.
- Limited analysis options beyond the basic methods.
- Graphics can look quite sloppy and are difficult to scale/export for publication/presentation.
A few epidemiologists used mainframe computers or struggled to assemble, program, and use microcomputers. Minicomputer software allowed CDC epidemiologists to develop questionnaires and analyze data through terminals.
Microcomputers and local area networks became standard public health tools. Epi Info and other database and statistics programs became standard equipment for public health. Epi Info™ was used for surveillance systems, disease investigations, surveys, clinical research, nutritional anthropometry, and veterinary and dental public health. Translations of the programs or manual appeared in 13 non-English languages. Worldwide copies exceeded 145,000 in 117 countries.
Remote areas of the world, starved for scientific information, suddenly began to share information with scientists in major capitals via the Internet. The Internet became the major route for distribution of Epi Info™, and approximately 400 users shared information via the Epi Info™ LISTSERV Discussion Group. The Epi Info™ Hotline began to serve users worldwide.
EIS Officers and summer students at CDC regularly learn to process data after 1 or 2 days of instruction. More than half of U.S. households have computers. Epi Info 2000 for Windows 95, 98, and NT will bring the benefits of hands-on questionnaire creation, database management, statistics, mapping and graphing to Windows, with Internet enhancements to follow.
In January of 2009 Epi Info 7 was released for Windows XP, Vista and Ubuntu. Major changes included, a change in language to Visual C# and the addition of mySQL and SQL Server database support.
iOS interface for uploading and adding data is introduced. Andriod application is added and included ability to upload data, and use calculators such as the 2x2 and MxN analyses.
- Form Designer – Form Designer and the Enter modules work together to design the data entry process and collect data. Form Designer is the tool used to design the survey, questionnaire, or form, tailor the data entry process, and specify the tab sequence. It is where you customize any data validation you want to occur when the form receives data in the Enter tool.
- Enter Data – The Enter program displays Forms constructed in Form Designer.
- Data Packager – The Epi Info Data Packager tool provides an easy way to share data with other users or to merge data collected by multiple users into a single database for analyses. The Data Packager does this by offering the option to package and export, as well as import data from Epi Info projects.
- Compatibility with industry standards, including:
Microsoft Access and other SQL and ODBC databases Visual Basic, Version 6 Output as HTML web pages
- Classic Analysis - Classic Analysis manipulates, manages, and analyzes data. It acts as a statistical toolbox providing many ways to transform data and perform statistical analyses. Data can be selected, sorted, listed, or manipulated with a series of commands, functions, and operators. Available statistics include frequencies, means, and more advanced processes (i.e., Kaplan-Meier Survival Classic Analysis and Logistic Regression).
- Maps - Maps is a versatile tool that geographically displays data on a map. The Maps tool has the ability to display multiple views from the same dataset. Datasets can be filtered or shown over a series of time using features in the Maps tool. Users can tailor these features to create a customized map containing public health data.
- Translation- Translation of Epi Info 7 programs, help files, and exercises into non-English languages is formulated by placing the translated phrase of all English phrases used in the programs in an MS Access.
- Web Survey- Web Survey System allows the survey designer to collect information from participants over the internet.
- Nutritional Anthropometry- Tools used to collect, analyze, and graph child growth data. Among these tools are a data entry form to calculate z-scores and percentiles as data are entered, growth charting capabilities in the Visual Dashboard, and several nutrition functions in Classic Analysis that you can use to add z-scores and percentiles to existing sets of data.
- Stat Calc- StatCalc is an epidemiologic calculator that produces statistics from summary data. Three types of calculations are offered:
- Statistics from 2-by-2 to 2-by-9 tables similar to those produced in Analysis. Both single and stratified 2-by-2 tables can be analyzed to produce odds ratios and risk ratios (relative risks) with confidence limits, several types of chi square tests, Fisher exact tests, Mantel-Haenszel summary odds ratios and chi squares, and associated p-values.
- Sample size and power calculations include Population Survey, Cohort or Cross-Sectional, and Unmatched Case-Control Study.
- Chi-square for trend by the Mantel extension of the Mantel-Haenszel summary odds ratio and chi square. This tests for the presence of a trend in dose response or other case control studies where a series of increasing or decreasing exposures is being studied.
OpenEpi - is a third party provider that supplements Epi Info with addional computations. OpenEpi is free and open source software that provides statistics for counts and measurements in descriptive and analytic studies, stratified analysis with exact confidence limits, matched poor and person-time analysis sample size and power calculations, random numbers, sensitivity, specificity and other evaluation statistics, R x C tables, chi-square for dose-response, and links to other useful sites. 
ActivEpi - Is a free supporting text for Epidemiologist and and users of the Epi Info that explains concepts and methods for teaching epidemiology 
In 2014 Epi Info was successfully used in New Guinea to locate people exposed to Ebola. http://www.cdc.gov/media/releases/2014/p0429-new-software.html
The Future of Epi Info
Version 7 is in continuing development as an open source project. Source code is available at Epi Info's Codeplex website. Web-based data entry, web-based analysis, and mobile data collection tools are currently available and will see continued improvement in 2016 and beyond. As the use of cloud computing increases Epi Info is also adapting to meet the needs of Public Health Informatics as well as Epidemiologist. Because of the worldwide use Epi Info faces many challenges in meeting the needs of so many public health professionals there will likely be changes to come in the interface and also the functionality.
- Dean 1999, p.17.
- CDC Epi Info Museum
- CDC Epi Info User Guide
- Dean, Andrew G. "Epi Info and Epi Map." Journal of Public Health Management and Practice 5.4 (1999): 54-56. Web. 20 Apr. 2016.
Submitted by Amy Hale