Table 4:
Input Parameters Associated With the Natural History of Major Depressive Disorder: Probabilities and Risks
| Model Parameter | Mean | Distribution | Source |
|---|---|---|---|
| Probabilities/Rates | |||
| Probability of MDD, by disease severity, no prior episode: | NA | Ferrari et al, 201374 | |
| Mild MDD | 0.68 | ||
| Moderate to severe MDD | 0.32 | ||
| Probability of MDD, by disease severity, with prior episode: | NA | Hardeveld et al, 201399 | |
| Mild MDD | 0.24 | ||
| Moderate to severe MDD | 0.76 | ||
| Probability of dropout, acute phase: | NA | Koeser et al, 201569 | |
| CBT only | 0.18 | ||
| CBT plus pharmacotherapy | 0.23 | ||
| Pharmacotherapy only | 0.30 | ||
| No treatment | 0.29 | ||
| Probability of being not well after dropout | 0.33 | Assumption, expert consultation | |
| Probability of no response, acute phase | NA | Koeser et al, 201569 | |
| CBT only | 0.23 | ||
| CBT plus pharmacotherapy | 0.18 | ||
| Pharmacotherapy only | 0.70 | ||
| Probability of response (no relapse), continuation phase | NA | Koeser et al, 201569 | |
| CBT only | 0.69 | ||
| CBT plus pharmacotherapy | 0.75 | ||
| Pharmacotherapy only | 0.70 | ||
| No treatment | 0.43 | ||
| Annual rate of recurrence, year 1, maintenance phase | 0.15 | NA | Eaton et al, 2008100 |
| Annual rate or recurrence, long-term | NA | Eaton et al, 2008100 | |
| Year 2 | 0.20 | ||
| Year 4 | 0.75 | ||
| Year 5 | 0.70 | ||
| Year 10 | 0.50 | ||
| Annual rate or recurrence, long term, after 6 months of remissiona | NA | Hardeveld et al, 201399 | |
| Year 1 | 0.025 | ||
| Year 2 | 0.045 | ||
| Year 5 | 0.13 | ||
| Year 10 | 0.23 | ||
| Year 15 | 0.23 | ||
| Year 20 | 0.42 | ||
| Rate of hospitalization | 0.10 | NA | Health Quality Ontario 201695 |
| Background rate of death | Ontario life tables | NA | Statistics Canada 2011104 |
| Rate of death by suicide | NA | Khan et al, 2003103; Khan and Schwartz 2007102 | |
| General population | 0.000166 | ||
| Patients with depression | 0.001 | ||
| Patients with chronic/complex depression | 0.0024 | ||
| Risks | Risk Ratio (95% CI) | Distribution | Source |
| Relative risk of recurrent MDD, by age of disease onset, for each additional year | 0.96 (0.93–0.97) |
Normalb (log-odds ratio) |
Eaton et al, 2008100 |
| Relative risk of recurrent MDE, for each additional episode | 1.18 (1.06–1.31) |
Normalb (log-odds ratio) |
Mueller et al, 1999101 |
Abbreviations: CBT, cognitive behavioural disorder; CI, confidence interval; MDD, major depressive disorder; MDE, major depressive episode; NA, not applicable.
a
Used in sensitivity scenario analysis only.
b
Distributions assigned in probabilistic sensitivity analysis.