Table 3 Power to detect given effect sizes (HRs) for associations between exposures with a prevalence of 10% and 20%, for the outcomes of dementia and stroke.
From: The protocols for the 10/66 dementia research group population-based research programme
Minimum Hazard Ratio to be detected | Power for detecting association with 10% exposure prevalence | Power for detecting an association with 20% exposure prevalence | ||
|---|---|---|---|---|
Outcome1,2 | Dementia | Stroke | Dementia | Stroke |
2.5 | 100% | 99.8% | 100% | 100% |
2.0 | 96.4% | 90.9% | 99.8% | 98.8% |
1.8 | 86.0% | 75.8% | 97.5% | 92.8% |
1.5 | 48.8% | 39.3% | 71.0% | 59.5% |