Table 23:
Sensitivity Analysis, Sequential Approach: Change in Utility Weight Associated With Guided iCBT
| Strategy | Mean Costs, $a | Mean QALYs | Incremental Costs, $a,b | Incremental QALYsc | ICER, $/QALY Gaineda | ICER, cont. $/QALY Gaineda,d |
|---|---|---|---|---|---|---|
| Unguided iCBT | 274.62 | 0.777 | — | — | — | — |
| Usual care | 409.40 | 0.787 | 134.79 | 0.009 | 38,931 | |
| Guided iCBT | 1,666.86 | 0.81701 | 1,257.46 | 0.030 | 39,184 | Extended dominance |
| Group CBT | 1,690.15 | 0.81704 | 23.29 | 0.00003 | 39,162d | 42,700 |
| Individual CBT | 2,654.08 | 0.8266 | 963.93 | 0.0096 | 38,678 | 56,115 |
Abbreviations: CBT, cognitive behavioural therapy; iCBT, internet-delivered CBT; ICER, incremental cost-effectiveness ratio; QALY, quality-adjusted life-year.
a
All costs in 2018 Canadian dollars. No discounting was done because of the 12-month time horizon.
b
Incremental cost = average cost (strategy of guided CBT) – average cost (strategy of usual care).
c
Incremental effect = average effect (strategy of guided CBT) – average effect (strategy of usual care).
d
The ICER of group CBT vs. usual care changed to $42,700/QALY after exclusion of guided iCBT by extended dominance.
Note: Results may appear incorrect because of rounding.