Table 2.
Primary and secondary outcomes at 12 months
| CBT | BA |
Observed data only |
Observed and imputed data |
||||
|---|---|---|---|---|---|---|---|
| Between-group difference | p value | Between-group difference | p value | ||||
| Primary outcome | |||||||
| PHQ-9 | |||||||
| Baseline | 17·4 (4·8); 219 | 17·7 (4·8); 221 | .. | .. | |||
| mITT | 8·4 (7·5); 189 | 8·4 (7·0); 175 | 0·1 (−1·3 to 1·5)* | 0·89 | 0·2 (−1·1 to 1·7)* | 0·80 | |
| PP | 7·9 (7·3); 151 | 7·8 (6·5); 135 | 0·0 (−1·5 to 1·6)* | 0·99 | 0·0 (−1·6 to 1·6)* | 0·99 | |
| Secondary outcomes | |||||||
| GAD-7 | |||||||
| Baseline | 12·6 (5·1); 219 | 12·7 (5·1); 221 | .. | .. | |||
| mITT | 6·3 (6·0); 176 | 6·4 (5·9); 161 | −0·1 (−1·0 to 1·3)* | 0·82 | 0·0 (−1·3 to 1·4)* | 0·96 | |
| PP | 6·0 (5·8); 146 | 5·9 (5·5); 129 | 0·01 (−1·3 to 1·2)* | 0·95 | −0·4 (−1·7 to 1·0)* | 0·60 | |
| SCID number of depression-free days | |||||||
| Baseline | .. | .. | .. | .. | |||
| mITT | 129 (58); 160 | 120 (56); 150 | 9 (−3 to 23)* | 0·13 | 7 (−7 to 20)* | 0·27 | |
| PP | 132 (55); 138 | 119 (55); 125 | 13 (0 to 26)* | 0·06 | 8 (−4 to 21)* | 0·21 | |
| SF-36v2 PCS | |||||||
| Baseline | 50·1 (13·1); 65 | 51·4 (11·9); 69 | .. | .. | |||
| mITT | 48·1 (12·2); 168 | 49·9 (11·6); 150 | 1·6 (−1·0 to 4·2)† | 0·22 | 1·4 (−1·1 to 4·0)† | 0·27 | |
| PP | 48·0 (12·2); 144 | 49·9 (12·0); 125 | 1·6 (−1·3 to 4·4)† | 0·28 | 1·3 (−1·5 to 4·1)† | 0·36 | |
| SF-36v2 MCS | |||||||
| Baseline | 23·2 (9·4); 65 | 22·5 (7·8); 69 | .. | .. | |||
| mITT | 41·7 (14·1); 168 | 41·6 (14·0); 150 | 0·0 (−3·0 to 3·0)† | 0·99 | 0·0 (−2·9 to 2·8)† | 0·97 | |
| PP | 42·9 (13·6); 144 | 42·3 (13·3); 125 | −0·5 (−3·7 to 2·7)† | 0·77 | −0·6 (−3·8 to 2·7)† | 0·73 | |
Data are mean (SD); n or mean (95% CI). CBT=cognitive behavioural therapy. BA=behavioural activation. PHQ-9=Patient Health Questionnaire 9. mITT=modified intention to treat. PP=per protocol. GAD-7=Generalized Anxiety Disorder 7. SCID=Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. SF-36v2=36-Item Short Form Survey version 2. PCS=physical component summary. MCS=mental component summary.
Models adjusted for baseline outcome score and stratification variables (symptom severity [PHQ-9 score of <19 vs ≥19], site [Devon, Durham, or Leeds], and antidepressant use [use or not]).
Models adjusted for stratification variables, but not baseline outcome score because of substantial missing data.