Table 5.
Model input parameters
| Parameter | Valuesa
Mean (std. error) |
Probability Distribution type for PSA |
Source |
|---|---|---|---|
| Prior probabilities | |||
| Probability of Rx treatment intervention arm | 0.469 (0.021) | Beta | 19 |
| Probability of Rx treatment control arm | 0.352 (0.016) | Beta | 19 |
| Probability of low bone mass | 0.374 (0.012) | Beta | 19 |
| Initial health state proportions | |||
| Post-upper extremity fracture | 0.691 (0.005) | Beta | 19 |
| Post-spine fracture | 0.051 (0.003) | Beta | 19 |
| Post-pelvis fracture | 0.043 (0.002) | Beta | 19 |
| Post-other fracture | 0.215 (0.005) | Beta | 19 |
| Re-fracture probabilities | |||
| Prior upper extremity fracture | |||
| Upper extremity fracture | 0.007 (0.001) | Beta | 17, 30 |
| Spine fracture | 0.006 (0.001) | Beta | 17, 30 |
| Hip fracture | 0.004 (0.001) | Beta | 17, 30 |
| Prior spine fracture | |||
| Upper extremity fracture | 0.011 (0.003) | Beta | 17, 30 |
| Spine fracture | 0.004 (0.001) | Beta | 17, 30 |
| Hip fracture | 0.007 (0.002) | Beta | 17, 30 |
| Prior pelvis/hip fracture | |||
| Upper extremity fracture | 0.017 (0.004) | Beta | 17, 30 |
| Spine fracture | 0.010 (0.003) | Beta | 17, 30 |
| Hip fracture | 0.014 (0.004) | Beta | 17, 30 |
| Prior other fracture | |||
| Upper extremity fracture | 0.002 (0.0002) | Beta | 17, 30 |
| Spine fracture | 0.002 (0.0001) | Beta | 17, 30 |
| Hip fracture | 0.001 (0.0001) | Beta | 17, 30 |
| Relative risk of fracture following treatment | |||
| Spine fracture | 0.520 (0.114) | Beta | 31 |
| Non-spine fracture | 0.510 (0.150) | Beta | 31 |
| Other treatment-related parameters | |||
| Persistence of treatment (probability at 1 year) | 0.604 (0.071) | Beta | 33 |
| Continuation of treatment effect following discontinuation of treatment (years) | Declines over 5 years to zero | Fixed | 32 |
| Mortality | |||
| Probability of all-cause death | Age-specific | ||
| 50 years of age | 0.003 (0.0002) | Beta | 42 |
| 90 | 0.150 (0.005) | Beta | 42 |
| Probability of death in year after hip fracture | Age-specific | ||
| 50 years of age | 0.034 (0.002) | Beta | 25, 42 |
| 90 | 0.258 (0.009) | Beta | 25, 42 |
| Cost ($ per patient per year, except where noted) | |||
| Intervention | 44.34 (2.79) | Gamma | 19 |
| BMD ($ per test) | 119.12 | Fixed | 36 |
| Bisphosphonate treatment | 131.28 | Fixed | 35 |
| Physician visit ($ per visit) | 35.91 | Fixed | 36 |
| Upper extremity fracture | 1397 (70) | Gamma | 36, 38, 39 |
| Upper extremity fracture post-pelvis fracture | 13,854 (693) | Gamma | 36, 38–40 |
| Spine fracture | 1662 (83) | Gamma | 36, 38, 39 |
| Spine fracture post-pelvis fracture | 14,041 (702) | Gamma | 36, 38–40 |
| Hip fracture | 38,332 (1917) | Gamma | 36, 38–40 |
| Late post-hip fracture cost | 12,357 (618) | Gamma | 36, 38–40 |
| Utility | |||
| General population utility score | Age-specific | ||
| 50–59 years | 0.84 (0.013) | Beta | 25 |
| 60–69 years | 0.82 (0.013) | Beta | 25 |
| 70–79 years | 0.80 (0.018) | Beta | 25 |
| 80+ years | 0.74 (0.034) | Beta | 25 |
| Utility weight multipliers | |||
| Hip fracture (1 year post-fracture) | 0.70 (0.035) | Beta | 43 |
| Hip fracture (subsequent years) | 0.80 (0.080) | Beta | 43 |
| Spine fracture | 0.59 (0.065) | Beta | 43 |
| Upper extremity fracture | 0.96 (0.048) | Beta | 43 |
| Discount rate (%) | 3.0 | Fixed | b |
aCosts are expressed in 2014 Canadian dollars (multiply by 0.905 to convert to US dollars [26])
bAssumed