Comparison 1. MI versus no MI (assessment only and alternative intervention) at ≥ 4 months follow‐up.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Quantity of alcohol consumed	33	7971	Std. Mean Difference (Random, 95% CI)	‐0.11 [‐0.15, ‐0.06]
2 Frequency of alcohol consumption	17	4377	Std. Mean Difference (Random, 95% CI)	‐0.14 [‐0.21, ‐0.07]
3 Binge drinking	21	5479	Std. Mean Difference (Random, 95% CI)	‐0.04 [‐0.09, 0.02]
4 Alcohol problems	25	6868	Std. Mean Difference (Random, 95% CI)	‐0.08 [‐0.17, ‐0.00]
5 Average BAC	5	901	Std. Mean Difference (IV, Random, 95% CI)	‐0.05 [‐0.18, 0.08]
6 Peak BAC	13	2790	Std. Mean Difference (IV, Random, 95% CI)	‐0.12 [‐0.20, ‐0.05]
7 Drink‐driving	4	1205	Std. Mean Difference (Random, 95% CI)	‐0.13 [‐0.36, 0.10]
8 Risky behaviour	7	1579	Std. Mean Difference (Random, 95% CI)	‐0.15 [‐0.31, 0.01]