Table 3.
Effectiveness (Nonvertebral Fractures Within 12 Months) Compared to Treatment with Alendronate, by Method of Confounder Adjustment, and Amount of Deviation From our Base Estimate
| Risedronate, N=8,718 | Calcitonin, N=8,372 | Raloxifene, N=5,038 | |||||||
|---|---|---|---|---|---|---|---|---|---|
| HR | 95% CI | % deviation† | HR | 95% CI | % deviation† | HR | 95% CI | % deviation† | |
| No. events, rate per 100 person-years follow-up | No. events=183, rate=2.28 | No. events=309, rate=4.03 | No. events=111, rate=2.31 | ||||||
| Unadjusted | 1.00 | 0.84, 1.19 | +1.0 | 1.77 | 1.53, 2.05 | +28.3 | 1.01 | 0.82, 1.25 | −13.2 |
| Published estimate (single model EPS + covariates9) | 1.01 | 0.85, 1.21 | +2.4 | 1.40 | 1.20, 1.63 | +1.2 | 1.18 | 0.96, 1.46 | +1.0 |
| Conventional multivariable model (base estimate) | 0.99 | 0.83, 1.19 | 0.0 | 1.38 | 1.18, 1.61 | 0.0 | 1.17 | 0.95, 1.45 | 0.0 |
| Exposure propensity score (EPS) | |||||||||
| Single model EPS | 1.00 | 0.84, 1.20 | +1.4 | 1.43 | 1.24, 1.67 | +3.9 | 1.18 | 0.95, 1.45 | +0.4 |
| Separate model EPS, restricted to overlap‡ | 0.98 | 0.82, 1.18 | −0.9 | 1.41 | 1.21, 1.65 | +2.4 | 1.13 | 0.91, 1.41 | −3.2 |
| Disease Risk Score (DRS) | |||||||||
| Full cohort DRS, restricted to DRSf overlap, N=43,066 | 1.00 | 0.84, 1.19 | +1.3 | 1.48 | 1.28, 1.71 | +7.1 | 1.18 | 0.96, 1.46 | +1.2 |
| Unexposed DRS, restricted to overlap, N=43,057 | 0.99 | 0.83, 1.18 | 0.0 | 1.56 | 1.35, 1.81 | +13.1 | 1.08 | 0.88, 1.34 | −7.4 |
*
alendronate group, N=21,007; events=448, rate=2.28 per 100 person-years of follow-up
†
% deviation calculated as the difference between the observed hazard ratio and the “base estimate” hazard ratio, divided by the “base estimate” hazard ratio, multiplied by 100
‡
Sample size: risedronate and alendronate (N=29,489), calcitonin and alendronate (N=29,309), raloxifene and alendronate (N=25,001)