Comparison of OpenEpi confidence intervals for a sample mean to other public software programs.

| Mean, Std Deviation, (sample size) while population size (N=999,999,999) and 95% confidence intervals are held constant
| 150, 27.36 (n=268) | 10.89, 3.76 (n=20) | 1.56, 8.56 (n=100) | 1.56, 8.56 (n=30)
95% CI based on z-statistics | Confidence limits | Confidence limits | Confidence limits | Confidence limits
OpenEpi | 146.725, 153.275 | 9.34, 12.54* | -0.1176, 3.2376 | -1.503, 4.6229
EpiInfo6@ (DOS version) | 146.72, 153.28 | 9.34, 12.54* | -0.12, 3.24 | -1.5-4.62
95% CI based on t-statistics |  |  |  |
OpenEpi | 146.709, 153.291 | 9.1362, 12.6438 | -0.1385, 3.2585 | -1.6364, 4.7564
PEPI$ | 146.709, 153.291 | 9.1303, 12.6497 | -0.1385, 3.2585 | -1.6364, 4.7564

@ t-statistics is not available

$ z-value is not available.

* Normal approximation method not recommended due to small sample size.

PEPI: Abramson JH and Gahlinger PM (2001). Computer program for epidemiologists: PEPI version 4.0. Sagebrush Press, Salt Lake City. Used CONFINT.EXE version 4.0.

EpiInfo6 (DOS version). Epidemiology program office, CDC. (EpiInfo software downloaded from ‘www.cdc.gov’).