Comparison 1. Bupropion. Abstinence at 6m or greater follow‐up.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Bupropion versus placebo/control. Subgroups by length of follow‐up	44	13728	Risk Ratio (M‐H, Fixed, 95% CI)	1.62 [1.49, 1.76]
1.1 Twelve month follow‐up	27	9866	Risk Ratio (M‐H, Fixed, 95% CI)	1.59 [1.44, 1.76]
1.2 Six month follow‐up	17	3862	Risk Ratio (M‐H, Fixed, 95% CI)	1.69 [1.45, 1.97]
2 Bupropion versus placebo/control. Subgroups by clinical/recruitment setting	44	13728	Risk Ratio (M‐H, Fixed, 95% CI)	1.62 [1.49, 1.76]
2.1 Community volunteers	21	7524	Risk Ratio (M‐H, Fixed, 95% CI)	1.67 [1.49, 1.87]
2.2 People recruited from health care settings	18	3928	Risk Ratio (M‐H, Fixed, 95% CI)	1.60 [1.38, 1.86]
2.3 Community + health care settings	1	540	Risk Ratio (M‐H, Fixed, 95% CI)	1.33 [0.83, 2.13]
2.4 Health care professionals/ hospital staff	2	1002	Risk Ratio (M‐H, Fixed, 95% CI)	1.32 [0.98, 1.78]
2.5 People with a previously unsuccessful quit attempt using bupropion	2	734	Risk Ratio (M‐H, Fixed, 95% CI)	2.25 [1.29, 3.90]
3 Bupropion versus placebo. Subgroups by level of behavioural support	41	13012	Risk Ratio (M‐H, Fixed, 95% CI)	1.63 [1.49, 1.77]
3.1 Multisession group behavioural support	10	2001	Risk Ratio (M‐H, Fixed, 95% CI)	1.76 [1.44, 2.16]
3.2 Multisession individual counselling	30	10964	Risk Ratio (M‐H, Fixed, 95% CI)	1.60 [1.45, 1.76]
3.3 Low intensity support	1	47	Risk Ratio (M‐H, Fixed, 95% CI)	2.88 [0.32, 25.68]
4 Bupropion dose response. 300 mg/day versus 150 mg/day	3	2042	Risk Ratio (M‐H, Fixed, 95% CI)	1.08 [0.93, 1.26]
5 Bupropion and NRT versus NRT alone	12	3487	Risk Ratio (M‐H, Random, 95% CI)	1.19 [0.94, 1.51]
5.1 Patch alone	9	1774	Risk Ratio (M‐H, Random, 95% CI)	1.24 [0.84, 1.84]
5.2 Lozenge alone	2	1051	Risk Ratio (M‐H, Random, 95% CI)	1.21 [0.81, 1.81]
5.3 Choice of NRT	1	662	Risk Ratio (M‐H, Random, 95% CI)	0.97 [0.73, 1.28]
6 Bupropion for relapse prevention	7	1959	Risk Ratio (M‐H, Fixed, 95% CI)	1.15 [1.00, 1.33]
7 Bupropion versus NRT	8	4086	Risk Ratio (M‐H, Fixed, 95% CI)	0.96 [0.85, 1.09]
7.1 Patch	6	1634	Risk Ratio (M‐H, Fixed, 95% CI)	1.04 [0.84, 1.27]
7.2 Lozenge	2	694	Risk Ratio (M‐H, Fixed, 95% CI)	0.91 [0.67, 1.22]
7.3 Patch + lozenge	2	720	Risk Ratio (M‐H, Fixed, 95% CI)	0.74 [0.55, 0.98]
7.4 Choice of NRT	2	1038	Risk Ratio (M‐H, Fixed, 95% CI)	1.08 [0.87, 1.33]
8 Bupropion versus varenicline	4	1810	Risk Ratio (M‐H, Fixed, 95% CI)	0.68 [0.56, 0.83]
9 Bupropion for harm reduction	1		Risk Ratio (M‐H, Fixed, 95% CI)	Totals not selected
9.1 Reduction in cotinine >50% from baseline at 1y	1		Risk Ratio (M‐H, Fixed, 95% CI)	0.0 [0.0, 0.0]
9.2 Cessation at 6m	1		Risk Ratio (M‐H, Fixed, 95% CI)	0.0 [0.0, 0.0]