Comparison 4. MI versus other active intervention.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Extent of substance use	14		Std. Mean Difference (Random, 95% CI)	Subtotals only
1.1 Post‐intervention	2	185	Std. Mean Difference (Random, 95% CI)	‐0.07 [‐0.37, 0.23]
1.2 Short f‐u	12	2137	Std. Mean Difference (Random, 95% CI)	0.02 [‐0.07, 0.12]
1.3 Medium f‐u	6	1586	Std. Mean Difference (Random, 95% CI)	‐0.02 [‐0.16, 0.13]
1.4 Long f‐u	2	437	Std. Mean Difference (Random, 95% CI)	‐0.03 [‐0.21, 0.14]
2 Readiness to change	2	350	Std. Mean Difference (Random, 95% CI)	‐0.03 [‐0.24, 0.18]
3 Retention in treatment	5	447	Std. Mean Difference (Random, 95% CI)	0.01 [‐0.45, 0.47]