Comparison 5. Sub‐group: mode of intervention delivery.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Patient asked to set a quit date	8		Odds Ratio (M‐H, Random, 95% CI)	Subtotals only
1.1 One‐on‐one	4	2353	Odds Ratio (M‐H, Random, 95% CI)	7.52 [2.17, 26.12]
1.2 Group sessions	8	4332	Odds Ratio (M‐H, Random, 95% CI)	4.98 [1.79, 13.88]
2 Patient asked to make a follow‐up appointment	7		Odds Ratio (M‐H, Random, 95% CI)	Subtotals only
2.1 One‐on‐one	3	1135	Odds Ratio (M‐H, Random, 95% CI)	3.60 [0.86, 15.08]
2.2 Group sessions	6	2596	Odds Ratio (M‐H, Random, 95% CI)	2.74 [1.06, 7.08]
3 Number of smokers counselled	14		Odds Ratio (M‐H, Random, 95% CI)	Subtotals only
3.1 One‐on‐one	6	3762	Odds Ratio (M‐H, Random, 95% CI)	2.76 [1.27, 6.01]
3.2 Group sessions	12	7438	Odds Ratio (M‐H, Random, 95% CI)	2.47 [1.41, 4.30]
4 Number of smokers receiving self‐help material	9		Odds Ratio (M‐H, Random, 95% CI)	Subtotals only
4.1 One‐on‐one	3	1451	Odds Ratio (M‐H, Random, 95% CI)	6.09 [3.93, 9.44]
4.2 Group sessions	8	4407	Odds Ratio (M‐H, Random, 95% CI)	3.22 [1.36, 7.65]
5 Number of smokers receiving nicotine gum/replacement therapy	9		Odds Ratio (IV, Random, 95% CI)	Subtotals only
5.1 One‐on‐one	2	941	Odds Ratio (IV, Random, 95% CI)	0.88 [0.41, 1.87]
5.2 Group sessions	8	4498	Odds Ratio (IV, Random, 95% CI)	1.65 [0.68, 4.01]