Table 1 Characteristics of included studies (n = 37)

Number of patients

- Sum

7,024

- Median (min., max.)

143 (29, 707)

Recruitment

- Clinical

19

- Screening

16

- Mixed

2

Restricted to patients > 55 years

5

Diagnosis

- Major depression only

14

- Depression (mixed/not exactly specified)

16

- Mild/minor/subthreshold depression and/or dysthymia

7

Overall risk of bias

- High (high risk in one or more items)

13

- Unclear (no item high risk, < 3 low risk)

11

- Low (at least 3 low, none high risk)

13

Interventions

Psychological interventions

- Face-to-face cognitive behavioural psychotherapy (CBT; ≥ 6 sessions)

9

- Face-to-face other problem-solving treatment (PST; ≥ 6 sessions)

5

- Face-to-face interpersonal psychotherapy (≥ 6 sessions)

3

- Face-to-face psychodynamic therapy (≥ 6 sessions)

1

- Other face-to-face psychosocial interventions (≥ 6 sessions)

8

- Remote therapist-led CBT (≥ 6 sessions)

4

- Remote therapist-led PST (≥ 6 sessions)

2

- Guided self-help CBT (up to 4 contacts)

4

- No/minimal contact CBT (less than 30 minutes contact)

4

Pharmacotherapy

- Selective serotonin reuptake inhibitors (SSRI)

6

- Tricyclic antidepressants

3

- Individualized antidepressant

1

Combinations psychological interventions and pharmacotherapy

- Face-to-face CBT + SSRI

1

- Face-to-face PST + SSRI

1

- Face-to-face interpersonal therapy + SSRI

1

Contol interventions

- Placebo

3

- Usual care

27

Median length of treatment in weeks (min., max.)

12 (6, 26)

Median number of treatment sessions (min., max.)

8 (0, 20)

Data available for meta-analysis

Outcome response

34

Outcome remission

34

Outcome depression score data

36

Outcome total number of patients discontinuing the study

34