Comparison 5. Duration of combination therapy.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
5.1 Smoking cessation	2		Risk Ratio (M‐H, Fixed, 95% CI)	Subtotals only
5.1.1 16 weeks versus 8 weeks	1	637	Risk Ratio (M‐H, Fixed, 95% CI)	0.96 [0.75, 1.23]
5.1.2 6 weeks versus 2 weeks	1	987	Risk Ratio (M‐H, Fixed, 95% CI)	1.11 [0.94, 1.31]
5.2 Overall serious adverse events	3		Risk Ratio (M‐H, Fixed, 95% CI)	Totals not selected
5.2.1 26 weeks versus 8 weeks	1		Risk Ratio (M‐H, Fixed, 95% CI)	Totals not selected
5.2.2 16 weeks versus 8 weeks	1		Risk Ratio (M‐H, Fixed, 95% CI)	Totals not selected
5.2.3 6 weeks versus 2 weeks	1		Risk Ratio (M‐H, Fixed, 95% CI)	Totals not selected