Table 3.
Total costs per participant for internet-CBT and waitlist at baseline and post-treatment (10 weeks) in 2016 US$ (imputed estimates)
| Baseline | Post-treatment | Incremental difference post-treatment (i-CBT–waitlist) | P value for difference | |||
| i-CBT | Waitlist | i-CBT | Waitlist | |||
| Mean (SD) | Mean (SD) | Mean (SD) | Mean (SD) | 95% CI* | ||
| i-CBT intervention cost | ||||||
| Online platform maintenance | – (–) | – (–) | 69.61 (–) | – (–) | 69.61 (–) | – |
| Therapist time cost | – (–) | – (–) | 108.75 (46.7) | – (–) | 108.75 (96.15 to 121.35) | 0.00 |
| Total intervention cost | – (–) | – (–) | 178.36 (46.7) | – (–) | 178.36 (165.75 to 190.96) | 0.00 |
| Adolescents | ||||||
| Healthcare costs | ||||||
| Healthcare resources | 359.49 (89.68) | 243.71 (49.16) | 112.44 (35.85) | 84.33 (26.88) | 5.53 (−28.18 to 81.25176) | 0.82 |
| Medication | 10.21 (3.23) | 4.02 (0.94) | 1.31 (0.59) | 1.63 (0.53) | −2.47 (−3.91 to 120.74) | 0.61 |
| Total healthcare cost† | 369.7 (89.56) | 247.73 (49.12) | 113.75 (35.81) | 85.97 (26.95) | 9.76 (−23.44 to 87.66) | 0.67 |
| Productivity loss at school | ||||||
| School absence | 242.11 (53.17) | 188.52 (30.71) | 136.19 (38.47) | 149.17 (34.26) | 10.56 (−49.17 to 63.47) | 0.71 |
| Reduced efficiency at school | 281.83 (50.42) | 192.61 (37.89) | 161.15 (40.02) | 91.47 (20.3) | −0.17 (−24.01 to 42.81) | 0.99 |
| Total productivity loss at school | 523.94 (92.78) | 381.13 (56.32) | 297.34 (66.71) | 240.64 (42.49) | −4.84 (−53.44 to 72.12) | 0.88 |
| Parents | ||||||
| Productivity loss paid work | ||||||
| Absence from paid work | 0 (0) | 20.97 (17.67) | 0 (0) | 13.04 (13.04) | −11.16 (−11.16 to 0) | 0.99 |
| Reduced efficiency at work | 220.75 (94.28) | 149.22 (68.44) | 81.07 (41.78) | 95.37 (67.57) | −112.75 (−158.55 to 283.06) | 0.29 |
| Total productivity loss paid work | 220.75 (94.28) | 170.19 (69.67) | 81.07 (41.78) | 108.41 (72.87) | −122.88 (−138.93 to 318.94) | 0.21 |
| Productivity loss unpaid housework | ||||||
| Absence from unpaid housework | 1.76 (1.42) | 3.33 (3.33) | 0.31 (0.31) | 3.4 (2.78) | −0.37 (−0.63 to 3.47) | 0.53 |
| Reduced efficiency unpaid housework | 15.78 (9.36) | 7.9 (6) | 2.93 (1.75) | 2.96 (2.03) | 0.4 (−0.98 to 9.52) | 0.77 |
| Total productivity loss unpaid housework | 17.54 (9.39) | 11.23 (7.71) | 3.24 (1.98) | 6.36 (4.75) | 0.55 (−1.38 to 12.8) | 0.77 |
|
Total societal costs
Trial estimate Bootstrapped estimate |
1131.93 (237.4) – |
810.28 (135.94) – |
671.24 (93.71) – |
441.37 (114.73) – |
163.81 (48.85 to 332.55) 170.24 (63.14 to 315.04) |
0.002 |
| Health outcomes | ||||||
| PedsQL | 71.28 (14.96) | 74.90 (13.42) | 77.03 (14.10) | 74.39 (14.61) | 5.647 (1.82 to 9.46) | 0.005 |
| EQ-5D-Y-3L utilities Trial estimate Bootstrapped estimate |
0.7976 (0.0198) – |
0.8269 (0.0161) – |
0.8361 (0.0175) – |
0.8292 (0.0156) – |
0.0032 (0.0001 to 0.0063)‡ 0.0031 (0.0003 to 0.0061)‡ |
0.043 |
*Mean incremental costs and 95% CI estimated using generalised linear models adjusted for baseline estimates.
†Does not include intervention cost.
‡Values correspond to difference in total quality-adjusted life-year (QALY) gains over the trial period, estimated using the area under the curve method.
i-CBT, internet-delivered cognitive–behavioural therapy.