Case Control Study Sample Size Example. Example Conducted a case-control study to determine if there is an association between colon cancer and diet high fat diet coffee. DETERMINANTS OF SAMPLE SIZE 7 31 Risk factorintervention under study 7 32 Distribution of risk factorintervention in the population 9 33 Power and significance of the study 9 34 Casecontrol ratio 11 4.
In case control studies we usually calculate the odds ratio if you are also planning to do so your required sample size can be calculated by just putting in the values of Expected proportion. The resulting formula for the sample size for testing a difference in prevalence. 140857 18 Frequency matching Match 2-3 variables Example.
From the Epi Info main page select StatCalc.
Sample size for case-control studies using Cochrans statistic. Example 2 RC No RC TD 400 333 No TD 100 167 Tea drinkers TD. The sample sizes can also be computed for scalar interaction effects. Inputs are the expected proportion exposed in the controls the assumed odds ratio and the desired level of confidence and power for the detection of a significant difference between the.
