Table 2 Sample size estimations based on background incidence, case/comparator ratio and anticipated relative risk including continuity correction
From: Protocol for a drugs exposure pregnancy registry for implementation in resource-limited settings
1 case / 1 comparator | 1 case / 4 comparators | |||||||
|---|---|---|---|---|---|---|---|---|
RR to be detected : 2 | RR to be detected : 10 | RR to be detected : 2 | RR to be detected : 10 | |||||
Incidence in comparator group | Cases | Comparators | Cases | Comparators | Cases | Comparators | Cases | Comparators |
5% | 474 | 474 | 19 | 19 | 274 | 1096 | 10 | 40 |
1% | 2515 | 2515 | 121 | 121 | 1445 | 5780 | 61 | 244 |
0.1% | 25471 | 25471 | 1272 | 1272 | 14621 | 58484 | 628 | 2512 |