Comparison 2. Sub‐group: treatment type.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Patient asked to set a quit date	8	4332	Odds Ratio (M‐H, Random, 95% CI)	4.98 [1.79, 13.88]
1.1 Counselling plus NRT	6	3322	Odds Ratio (M‐H, Random, 95% CI)	7.45 [3.30, 16.85]
1.2 Counselling alone	2	1010	Odds Ratio (M‐H, Random, 95% CI)	1.22 [0.78, 1.92]
2 Patient asked to make a follow‐up appointment	7		Odds Ratio (M‐H, Random, 95% CI)	Totals not selected
2.1 Counselling plus NRT	4		Odds Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
2.2 Counselling alone	3		Odds Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
3 Number of smokers counselled	14	8531	Odds Ratio (M‐H, Random, 95% CI)	2.28 [1.41, 3.67]
3.1 Counselling plus NRT	9	5768	Odds Ratio (M‐H, Random, 95% CI)	2.66 [1.33, 5.32]
3.2 Counselling alone	5	2763	Odds Ratio (M‐H, Random, 95% CI)	1.71 [1.09, 2.68]
4 Number of smokers receiving self‐help material	9	4925	Odds Ratio (M‐H, Random, 95% CI)	3.52 [1.56, 7.91]
4.1 Counselling plus NRT	5	3165	Odds Ratio (M‐H, Random, 95% CI)	5.50 [2.45, 12.36]
4.2 Counselling alone	4	1760	Odds Ratio (M‐H, Random, 95% CI)	1.91 [0.56, 6.48]
5 Number of smokers receiving nicotine gum/replacement therapy	9	5073	Odds Ratio (M‐H, Random, 95% CI)	1.57 [0.72, 3.42]
5.1 Counselling plus NRT	6	4122	Odds Ratio (M‐H, Random, 95% CI)	1.78 [0.65, 4.91]
5.2 Counselling alone	3	951	Odds Ratio (M‐H, Random, 95% CI)	1.00 [0.66, 1.50]