Comparison 2. Non‐tailored self‐help vs no self‐help, pooling all studies.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Long‐term abstinence	31	28451	Risk Ratio (M‐H, Random, 95% CI)	1.06 [0.95, 1.19]
1.1 No contact/No materials for control	11	13241	Risk Ratio (M‐H, Random, 95% CI)	1.19 [1.03, 1.37]
1.2 No contact/Leaflet for control	6	7023	Risk Ratio (M‐H, Random, 95% CI)	0.87 [0.71, 1.07]
1.3 Face‐to‐face contact/No materials for control	3	1668	Risk Ratio (M‐H, Random, 95% CI)	1.35 [0.80, 2.26]
1.4 Face‐to‐face contact/Leaflet for control	1	1154	Risk Ratio (M‐H, Random, 95% CI)	1.42 [0.98, 2.04]
1.5 Advice/No materials for control	8	3581	Risk Ratio (M‐H, Random, 95% CI)	0.91 [0.66, 1.27]
1.6 Advice/Leaflet for control	3	1784	Risk Ratio (M‐H, Random, 95% CI)	1.18 [0.71, 1.95]