Table 2.
Distribution of randomization assignments among samples of patients with STEMI.
| Strategy | Decision rule | Circumstance 1: PCI* at 90 minutes vs. TT** at 30 minutes | Circumstance 2: PCI* at 120 minutes vs. TT** at 30 minutes | Circumstance 3: PCI* at 180 minutes vs. TT** at 15 minutes |
|---|---|---|---|---|
| Full sample (n = 2,781) | ||||
| Use 50% PI for δ for patient* | 50% PI < 0, treat w/TT** | 0% | 0% | 22% |
| 50% PI contains 0%, randomize | 60% | 93% | 78% | |
| 50% PI > 0, treat w/PCI** | 40% | 7% | 0% | |
| Total 100% | Total 100% | Total 100% | ||
| RR > 1.2 in favor of either treatment$ | TT predicted to be at least 20% better, treat with TT | 0% | 0% | 25% |
| Neither has ≥20% predicted benefit, randomize | 66% | 100% | 74% | |
| PCI predicted to be at least 20% better, treat with PCI | 34% | 0% | <1% | |
| Total 100% | Total 100% | Total 100% | ||
| Subset of patients from TPI trial (n = 1,037) | ||||
| Use 50% PI for δ for patient | 50% PI < 0, treat w/TT | 0% | 0% | 18% |
| 50% PI contains 0%, randomize | 62% | 92% | 82% | |
| 50% PI > 0, treat w/PCI | 38% | 8% | 0% | |
| Total 100% | Total 100% | Total 100% | ||
| RR > 1.2 in favor of either treatment | TT predicted to be at least 20% better, treat with TT | 0% | 0% | 20% |
| Neither has ≥20% predicted benefit, randomize | 70% | 100% | 79% | |
| PCI predicted to be at least 20% better, treat with PCI | 30% | 0% | <1% | |
| Total 100% | Total 100% | Total 100% | ||
*50% prediction interval (PI) for delta (d), where delta = predicted (PCI) survival benefit = p(live) with PCI minus p(live) with TT.
**PCI, percutaneous coronary intervention (angioplasty); TT, thrombolytic therapy.This is the relative risk (RR) of death with treatment of TT versus PCI. This estimate is based on the PCI–TPI model predictions with the published model alone. It does not use results of the 1,000 simulations. A RR > 1.2 (for PCI vs. TT or TT vs. PCI) indicates that the predicted mortality at least 20% higher for one treatment versus the other.