# OpenEpi, Version of December, 2003

## Test Results for SSCohort Module

Dataset # | Confidence, Power (%) | Ratio, Outcome in Unexp, in Exp | Compared with | Result
S-1 | 95,90 | 1, 0.03%, 0.015% | Snedecor & Cochran, Statistical Methods, Iowa State University, 1980, p. 130. Salk Trial Example, | Agreement (210171 vs. 210000, assuming that Snedecor and Cochran rounded off)
S-2 | 95,90 | 2, 30%, RR>=4 | Schlesselman, JJ, Case-Control Studies, Oxford Univ. Press, 1982 | Agreement
S-9 | 95,80 | 1, 5%,10% | Pezzullo JavaStat website. Proportion Difference Power/Sample Size Calculation http://members.aol.com/johnp71/proppowr.html | Agreement, with OpenEpi rounding up
S-8 | 99,80 | 1, 40%,60% | Pezzullo JavaStat website. Proportion Difference Power/Sample Size Calculation http://members.aol.com/johnp71/proppowr.html | Agreement, with OpenEpi rounding up
S-7a | 95,80 | 0.25, 5%,10% | Pezzullo JavaStat website. Proportion Difference Power/Sample Size Calculation http://members.aol.com/johnp71/proppowr.html | 1256 vs 1253 314 vs 313
S-7b | 95,80 | 0.25, 5%,10% | Epi Info Statcalc | 1256 vs 1253 314 vs 313

Testing by Andy Dean. .

Conclusions: OpenEpi sample size programs round results UP rather than to the nearest integer, since it is difficult to find 0.1 person to participate in a study. Agreement takes this into account.

These results are sufficient to remove the BETA labels from the programs, although further testing and comparison of important results with those from other programs is always in order. Please send us results of further testing so that we can add them to this list.