Table 1.
Model Input Data
| Variable | Base Case (95% CI) | Distribution | References |
|---|---|---|---|
| General inputs, % | |||
| Annual discount rate | 3 | – | 24 |
| Annual mortality probability | 0.479 (0.446 to 0.515) | Normal | 31, 44, 45 |
| First-line treatment variables | |||
| Initial remission probability | |||
| SGA, % | 39.7 (32.1 to 47.8) | Logit-normal | 32 |
| CBT, relative risk vs. SGA | 1.02 (0.76 to 1.37) | Log-normal | 7 |
| Initial response probability | |||
| SGA, % | 63.1 (55.3 to 70.3) | Logit-normal | 32 |
| CBT, relative risk vs. SGA | 1.11 (0.93 to 1.32) | Log-normal | 7 |
| Annual relapse probability | |||
| SGA, % | 38.1 (34.0 to 42.2) | Beta | 33 |
| CBT, relative risk vs. SGA | 0.73 (0.26 to 2.08) | Log-normal | 7, 34, 35 |
| Annual discontinuation due to adverse event probability | |||
| SGA, % | 24.9 (15.1 to 39.1) | Logit-normal | 7, 36–38 |
| CBT, relative risk vs. SGA | 0.40 (0.06 to 2.50) | Log-normal | 7 |
| Subsequent treatment variables | |||
| Initial remission probability(relative risk vs. first-line SGA) | |||
| Treatment 2 | 0.93 (0.86 to 1.00) | Log-normal | 31 |
| Treatment 3 | 0.77 (0.70 to 0.85) | Log-normal | 31 |
| Treatment 4 | 0.35 (0.27 to 0.45) | Log-normal | 31 |
| Treatments 5–9* | 0.33 (0.21 to 0.52) | Log-normal | 31 |
| Initial response probability (relative risk vs. first-line SGA) | |||
| Treatment 2 | 0.77 (0.73 to 0.81) | Log-normal | 31 |
| Treatment 3 | 0.48 (0.44 to 0.53) | Log-normal | 31 |
| Treatment 4 | 0.27 (0.21 to 0.33) | Log-normal | 31 |
| Treatment 5–9* | 0.26 (0.17 to 0.39) | Log-normal | 31 |
| Annual relapse probability, % | 38.1 (34.0 to 42.2) | Beta | 33 |
| Annual discontinuation due to adverse event probability, % | 24.9 (15.1 to 39.1) | Logit-normal | 7, 36–38 |
| Utility with depression | |||
| Remission | 0.85 (0.83 to 0.87) | Normal | 39 |
| Response | 0.72 (0.65 to 0.79) | Normal | 39 |
| Nonresponse, relapse, initiation | 0.58 (0.50 to 0.66) | Normal | 39 |
| Costs, $ | |||
| First-line treatment, per month | |||
| SGA, months 1–3 | 76 (46 to 105) | Normal | 12–14 |
| SGA, months 4+ | 28 (17 to 39) | Normal | 12–14 |
| CBT, months 1–3 | 280 (170 to 390) | Normal | 12, 40 |
| CBT, months 4+ | 140 (85 to 195) | Normal | 12, 40 |
| Other depression, per year | |||
| Treatment 1† | 6747 (6333 to 7161) | Normal | 41 |
| Treatment 2 | 8471 (8057 to 8884) | Normal | 41 |
| Treatment 3 | 8913 (7524 to 10 286) | Normal | 30 |
| Treatment 4 | 12 862 (12 331 to 13 377) | Normal | 30 |
| Treatment 5 | 12 753 (12 159 to 13 330) | Normal | 30 |
| Treatment 6 | 14 688 (13 830 to 15 531) | Normal | 30 |
| Treatment 7 | 15 984 (14 626 to 17 326) | Normal | 30 |
| Treatment 8 | 16 998 (14 907 to 19 074) | Normal | 30 |
| Treatment 9 | 18 185 (14 501 to 21 853) | Normal | 30 |
| Indirect (productivity), per year | |||
| Remission | 2099 (1359 to 2840) | Normal | 42, 43 |
| Response | 5848 (3499 to 8197) | Normal | 42, 43 |
| Nonresponse, relapse, initiation | 11 755 (8190 to 15 321) | Normal | 42, 43 |
CBT = cognitive behavioral therapy; SGA = second-generation antidepressant.
*
Remission and response probabilities from step 4 of the STAR*D (Sequenced Treatment Alternatives to Relieve Depression) trial are assumed to apply to treatments 5 to 9 in the model.
†
Other depression cost for treatment 1 excludes depression-related outpatient cost and depression-related pharmaceutical cost because they are accounted for separately in the first-line treatment cost. For subsequent treatments, these cost components are included.