Table 1: Sample size determination for the retrospective study.
|
Expected incidence in unexposed |
0.01 |
|
Assumed relative risk |
3.5 |
|
Confidence level |
0.95 |
|
Power |
0.8 |
|
Study type |
Cohort study |
|
Sample size per group |
549 |
|
Total sample size (both groups): |
1098 |