Table 3.

Results of the linear regression models based on intention-to-treat analyses

	β	95% CI	P value
Step 1: main effects
Intervention group
Control	Reference
Intervention	1.75	1.19 to 2.31	<0.001
PHQ-9 total score at baseline	0.55	0.43 to 0.66	<0.001
Age in years	0.01	−0.02 to 0.04	0.44
Sex
Male	Reference
Female	−0.38	−1.02 to 0.25	0.24
Education
High school (‘Abitur’, ie, reaching university entrance qualification)	Reference
Other	0.1	−0.51 to 0.71	0.75
Employment
Full-time or part-time employed	Reference
Not working	0.12	−0.47 to 0.71	0.69
Marital group
Married/in a stable relationship	Reference
Not living with a partner, including divorcees to widowers	−0.07	−0.96 to 0.82	0.87
Single	−0.32	−1.05 to 0.4	0.38
Frequency of episodes
1 episode	Reference
2–5 episodes	−0.12	−0.89 to 0.64	0.75
6–10 episodes	−0.86	−1.75 to 0.02	0.06
11–20 episodes	−0.91	−1.96 to 0.14	0.09
>20 episodes	−1.84	−3.05 to −0.63	0.003
Step 2: moderator effects
Intervention by age	0.01	−0.04 to 0.06	0.56
Intervention by sex	−0.05	−1.27 to 1.17	0.94
Intervention by education	0.89	−0.21 to 1.99	0.11
Intervention by employment	0.16	−0.95 to 1.27	0.77
Intervention by marital group (overall effect)			0.32
Intervention by frequency of episodes (overall effect)			0.95

P values marked in bold are significant at the p<0.05 level.

CI, confidence interval; PHQ-9, Patient Health Questionnaire-9.