Table 4.
Moderator effects: subgroup analysis (post-test)
| Outcome measure | Criteria | Subgroup (study) | n | Cohen’s d (95% CI) | Test for subgroup differences |
|---|---|---|---|---|---|
| Subjective well-being |
Self-selection |
Self-selected |
15 |
0.29 (0.18 – 0.39)*** |
Q=0.64, df=1 (p=.43) |
| |
|
Not self-selected |
13 |
0.38 (0.17 – 0.60)** |
|
| |
Duration |
<=4 weeks |
17 |
0.35 (0.18 – 0.52)*** |
Q=1.84, df=2 (p=.91) |
| |
|
<=8 weeks |
6 |
0.24 (0.10 - 0.39)** |
Slope=0.01, Z=0.14 (p=.89) |
| |
|
>8 weeks |
5 |
0.43 (0.17 – 0.68)** |
|
| |
Type |
Self help |
20 |
0.33 (0.20 – 0.46)*** |
Q=0.20, df=2 (p=.91) |
| |
|
Group |
5 |
0.38 (0.03 – 0.73)* |
|
| |
|
Individual |
3 |
0.41 (0.01 – 0.81)* |
|
| |
Recruitment |
Community |
6 |
0.29 (0.11 – 0.48)** |
Q=5.36, df=4 (p=.25) |
| |
|
Internet |
2 |
0.06 (−0.24 – 0.35)ns |
|
| |
|
Referral/hospital |
2 |
0.51 (0.08 – 0.95)* |
|
| |
|
University |
16 |
0.36 (0.19 – 0.53)*** |
|
| |
|
Organization |
2 |
0.62 (0.11-1.12)* |
|
| |
Psychosocial problems |
Specific psychosocial problems |
4 |
0.31 (0.09 – 0.52)** |
Q=0.10, df=1 (p=.76) |
| |
|
None |
24 |
0.35 (0.22 – 0.48)*** |
|
| |
Quality rating |
Low (1–2) |
16 |
0.29 (0.17 – 0.40)*** |
Q=2.41, df=2 (p=.30) |
| |
|
Medium (3–4) |
11 |
0.40 (0.19 – 0.61)*** |
Slope=−0.00, Z=0.08 (p=.94) |
| |
|
High (5–6) |
1 |
0.05 (−0.34 – 0.44)ns |
|
| Psychological well-being |
Self-selection |
Self-selected |
15 |
0.18 (0.05 – 0.30)** |
Q=0.32, df=1 (P=.57) |
| |
|
Not self-selected |
5 |
0.25 (0.04- 0.46) * |
|
| |
Duration |
<=4 weeks |
11 |
0.16 (0.07 – 0.25)*** |
Q=1.91, df=2 (p=.39) |
| |
|
<=8 weeks |
2 |
0.35 (−0.20 – 0.89)ns |
Slope=0.05, Z=0.95 (p=.34) |
| |
|
>8 weeks |
7 |
0.41 (0.03 – 0.79)* |
|
| |
Type |
Self help |
10 |
0.14 (0.05 – 0.23)** |
Q=3.76, df=2 (p=.15) |
| |
|
Group |
6 |
0.26 (0.08 – 0.44)** |
|
| |
|
Individual |
4 |
0.81 (−0.01 – 1.63)ns |
|
| |
Recruitment |
Community |
4 |
0.20 (−0.03 – 0.44)ns |
Q=7.04, df=4 (p=.13) |
| |
|
Internet |
5 |
0.09 (−0.03 – 0.21)ns |
|
| |
|
Referral/hospital |
4 |
0.91 (0.24 – 1.57)** |
|
| |
|
University |
5 |
0.22 (0.08 – 0.35)** |
|
| |
|
Organization |
2 |
0.18 (−0.43 – 0.78)ns |
|
| |
Psychosocial problems |
Specific psychosocial problems |
5 |
0.59 (0.00 – 1.18)* |
Q=1.93, df=1 (p=.17) |
| |
|
None |
15 |
0.17 (0.08 – 0.25)*** |
|
| |
Quality rating |
Low (1–2) |
10 |
0.32 (0.07 – 0.58)* |
Q=1.86, df=2 (p=.40) |
| |
|
Medium (3–4) |
9 |
0.15 (0.06 – 0.24)** |
Slope=−0.01, Z=−0.45 (p=.66) |
| |
|
High (5–6) |
1 |
0.29 (−0.11 – 0.68)ns |
|
| Depression |
Self-selection |
Self-selected |
12 |
0.20 (0.05– 0.36)* |
Q=1.73, df=1 (p=.19) |
| |
|
Not self-selected |
2 |
0.41 (0.15 – 0.66)** |
|
| |
Duration |
<=4 weeks |
7 |
0.15 (0.02 - 0.28)* |
Q=4.86, df=2 (p=.09) |
| |
|
<=8 weeks |
2 |
0.47 (−0.02 - 0.97)ns |
Slope=0.20, Z=2.32 (p=.02) |
| |
|
>8 weeks |
5 |
0.68 (0.15 – 1.21)* |
|
| |
Type |
Self help |
8 |
0.15 (0.03 – 0.27)* |
Q=6.99, df=2 (p=.03) |
| |
|
Group |
2 |
0.47 (−0.02 – 0.97)ns |
|
| |
|
Individual |
4 |
0.88 (0.29 – 1.47)** |
|
| |
Recruitment |
Community |
1 |
0.48 (−0.23 – 1.18)ns |
Q=15.76, df=4 (p<.01) |
| |
|
Internet |
5 |
0.11 (−0.02 – 0.23)ns |
|
| |
|
Referral/hospital |
3 |
1.14 (0.55 – 1.73)*** |
|
| |
|
University |
3 |
0.41 (0.17 – 0.65)** |
|
| |
|
Organization |
2 |
0.22 (−0.18 – 0.63)ns |
|
| |
Psychosocial problems |
Specific psychosocial problems |
5 |
0.78 (0.35 – 1.21)*** |
Q=7.65, df=1 (p=.01) |
| |
|
None |
9 |
0.16 (0.05 – 0.27)** |
|
| |
Quality rating |
Low (1–2) |
7 |
0.47 (0.26 – 0.67)*** |
Q=10.14, df=2 (p=.01) |
| |
|
Medium (3–4) |
6 |
0.15 (0.00 – 0.30)* |
Slope=−0.10, Z=−2.26 (p=.02) |
| High (5–6) | 1 | −0.17 (−0.56 – 0.22)ns |
* p<0.05; ** p<0.01; *** p<0.001; ns non-significant.
n = Number of studies.