Table 5 Meta-analysis with between-study subgroup analyses of variables related to study procedures and content of collaborative care

All studies

7

0.35

0.14 – 0.56

21.73

72.39

Country

0.031*

US

4

0.37

0.26 – 0.49

1.10

0.00

European

3

0.29

−0.31 – 0.89

15.98

87.50

Randomization procedure

0.031*

Patient randomization

4

0.37

0.26 – 0.49

1.10

0.00

Cluster randomization

3

0.29

−0.31 – 0.89

15.98

87.50

Recruitment method

0.65

Referral by professional

2

0.33

0.19 – 0.47

0.02

0.00

Systematic identification (or both)

5

0.38

0.05 – 0.71

21.51

81.41

Care manager

0.001*

Care manager

5

0.42

0.29 – 0.55

4.66

14.24

No care manager

2

0.13

−0.43 – 0.70

5.69

82.43

Intervention content

0.82

Psychological intervention (CBT) with/without medication management

5

0.42

0.29 – 0.55

4.66

14.24

Medication management alone

1

0.45

0.03 – 0.87

–

–

Not applicable

1

–

–

–

–

Stepped care

0.041*

Stepped care

2

0.57

0.06 – 0.53

1.58

36.85

No stepped care

5

0.29

0.16 – 0.99

15.97

74.95

Supervision frequency specialist-care manager

0.056

Ad hoc

1

0.73

0.37 – 1.09

–

–

Scheduled (i.e. at least 2-weekly)

4

0.36

0.25 – 0.48

1.03

0.00

Not applicable

2

–

–

–

–