Table 6.
BOLD Power Estimates (registry size = 5,000 patients)*
| Index Case Prevalence | ||||
|---|---|---|---|---|
| |
2% |
3% |
5% |
10% |
|
Number of Cases |
100 |
150 |
250 |
500 |
|
Effect Size (D) | ||||
|
RDQ† | ||||
| 1.5 |
- |
- |
61% |
88% |
| 2.0 |
- |
63% |
84% |
98% |
| 2.5 |
65% |
82% |
96% |
99% |
|
Pain NRS† | ||||
| 0.7 |
- |
52% |
74% |
96% |
| 1.0 |
65% |
82% |
96% |
99% |
| 1.3 |
87% |
96% |
99% |
99% |
|
Incremental Cost per QALY Gain < $50,000†† | ||||
| $500 / 0.03 DQALY |
- |
- |
- |
38% |
| $500 / 0.06 DQALY |
45% |
61% |
82% |
98% |
| $800 / 0.03 DQALY |
- |
- |
- |
21% |
| $800 / 0.06 DQALY |
36% |
51% |
72% |
95% |
|
Rare Events (Surgery, Complication, or Binary Event Rate)** | ||||
| 2% Incidence Rate | ||||
| RR = 1.5 |
- |
- |
- |
- |
| RR = 2.0 |
- |
- |
- |
62% |
| RR = 2.5 |
- |
- |
60% |
88% |
| 5% Incidence Rate | ||||
| RR = 1.5 |
- |
- |
- |
51% |
| RR = 2.0 |
- |
51% |
73% |
95% |
| RR = 2.5 | - | 79% | 95% | 99% |
*Comparisons where power estimates are below 50% are not provided
† Conservatively assumes 1:1 case:control ratio, SD estimates of 7.5 and 3.0 for RDQ and Pain NRS respectively.
†† Conservatively assumes 1:1 case to control ratio, calculated for one-year time period, cost standard deviations of $4,000 per group, QALY standard deviations of 0.2 per group based on EQ-5D and 6-month effect improvement, and a positive correlation of 0.3 between costs and changes in EQ-5D [47]. Assuming a negative correlation did not affect power substantially.
**Assumes 3:1 matching of controls to index cases.