Table 2.
Summary of between-group differences in primary trial outcome
| Outcome measure | Intention to treat sample | Per protocol sample | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| TAU | TD-GCBT | Difference | TAU | TD-GCBT | Difference | |||||||||||
| No. M (s.d.) | No. M (s.d.) | Morris' d p | No. M (s.d.) | No. M (s.d.) | Morris' d p | |||||||||||
| GAD-7 | ||||||||||||||||
| Baseline | 534 | – | 527 | – | – | – | – | 534 | 12.1 | (4.7) | 527 | 12.5 | (4.6) | – | 0.264 | |
| Post-treatment | 534 | 9.5 | (5.4) | 527 | 6.8 | (4.7) | −0.65 | <0.001 | 316 | 10.2 | (5.5) | 315 | 6.0 | (4.3) | −1.01 | <0.001 |
| 3 months | 534 | 8.7 | (5.3) | 527 | 7.3 | (5.0) | −0.38 | <0.001 | 238 | 8.9 | (5.4) | 273 | 6.7 | (4.9) | −0.62 | <0.001 |
| 6 months | 534 | 8.6 | (5.4) | 527 | 6.9 | (5.1) | −0.45 | <0.001 | 204 | 8.8 | (5.7) | 229 | 6.2 | (4.9) | −0.78 | <0.001 |
| 12 months | 534 | 8.3 | (5.7) | 527 | 6.6 | (5.4) | −0.44 | <0.001 | 180 | 8.7 | (5.8) | 208 | 5.8 | (5.3) | −0.91 | <0.001 |
| PHQ-9 | ||||||||||||||||
| Baseline | 534 | – | – | 527 | – | – | – | – | 534 | 13.5 | (5.4) | 527 | 13.7 | (5.3) | – | 0.443 |
| Post-treatment | 534 | 10.8 | (6.4) | 527 | 8.0 | (5.7) | −0.58 | <0.001 | 316 | 11.5 | (6.6) | 315 | 7.0 | (5.2) | −0.92 | <0.001 |
| 3 months | 534 | 10.2 | (6.4) | 527 | 8.4 | (6.0) | −0.39 | <0.001 | 238 | 10.3 | (6.5) | 273 | 7.8 | (6.0) | −0.60 | <0.001 |
| 6 months | 534 | 9.8 | (6.4) | 527 | 7.9 | (6.1) | −0.40 | <0.001 | 205 | 10.0 | (6.6) | 228 | 7.3 | (6.1) | −0.75 | <0.001 |
| 12 months | 534 | 9.4 | (6.3) | 527 | 7.8 | (5.9) | −0.36 | <0.001 | 180 | 9.7 | (6.5) | 208 | 7.1 | (6.2) | −0.61 | <0.001 |
| PHQ-15 | ||||||||||||||||
| Baseline | 534 | – | – | 527 | – | – | – | – | 534 | 14.0 | (4.8) | 527 | 14.3 | (4.9) | – | 0.388 |
| Post-treatment | 534 | 11.7 | (5.2) | 527 | 9.9 | (5.4) | −0.40 | <0.001 | 316 | 12.1 | (5.2) | 315 | 9.1 | (5.3) | −0.65 | <0.001 |
| 3 months | 534 | 11.4 | (5.1) | 527 | 10.1 | (5.3) | −0.32 | <0.001 | 238 | 11.7 | (5.0) | 273 | 9.5 | (5.4) | −0.49 | <0.001 |
| 6 months | 534 | 11.1 | (5.3) | 527 | 9.8 | (5.6) | −0.31 | <0.001 | 205 | 11.5 | (5.3) | 228 | 9.2 | (5.7) | −0.59 | <0.001 |
| 12 months | 534 | 10.7 | (5.6) | 527 | 9.4 | (5.6) | −0.32 | <0.001 | 180 | 11.7 | (5.6) | 208 | 8.8 | (5.7) | −0.57 | <0.001 |
GAD-7, generalized anxiety disorder-7; M, mean; PHQ-9, Patient Health Questionnaire-9; PHQ-15, Patient Health Questionnaire-15, TAU, treatment-as-usual; TD-GCBT, transdiagnostic group cognitive-behavioural therapy; s.d., standard deviation.