Comparison 1. Nicotine EC versus NRT.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1.1 Smoking cessation	6	2378	Risk Ratio (M‐H, Fixed, 95% CI)	1.63 [1.30, 2.04]
1.1.1 Not selected on pregnancy	5	2059	Risk Ratio (M‐H, Fixed, 95% CI)	1.62 [1.29, 2.04]
1.1.2 Pregnant population	1	319	Risk Ratio (M‐H, Fixed, 95% CI)	1.78 [0.45, 6.97]
1.2 Adverse events	4	1702	Risk Ratio (M‐H, Fixed, 95% CI)	1.02 [0.88, 1.19]
1.2.1 4 weeks	1	29	Risk Ratio (M‐H, Fixed, 95% CI)	0.74 [0.31, 1.73]
1.2.2 6 months	2	563	Risk Ratio (M‐H, Fixed, 95% CI)	1.01 [0.82, 1.24]
1.2.3 3 months after end of pregnancy	1	1110	Risk Ratio (M‐H, Fixed, 95% CI)	1.05 [0.84, 1.31]
1.3 Serious adverse events	5	2411	Risk Ratio (M‐H, Fixed, 95% CI)	1.12 [0.82, 1.52]
1.3.1 4 weeks	1	29	Risk Ratio (M‐H, Fixed, 95% CI)	Not estimable
1.3.2 6 months	2	563	Risk Ratio (M‐H, Fixed, 95% CI)	1.53 [0.81, 2.88]
1.3.3 1 year	1	698	Risk Ratio (M‐H, Fixed, 95% CI)	1.37 [0.77, 2.41]
1.3.4 3 months after end of pregnancy	1	1121	Risk Ratio (M‐H, Fixed, 95% CI)	0.83 [0.52, 1.31]
1.4 Carbon monoxide (ppm)	3	191	Mean Difference (IV, Fixed, 95% CI)	‐2.74 [‐5.42, ‐0.07]
1.4.1 Absolute values at follow‐up	1	110	Mean Difference (IV, Fixed, 95% CI)	‐1.87 [‐5.15, 1.41]
1.4.2 Change from baseline	2	81	Mean Difference (IV, Fixed, 95% CI)	‐4.47 [‐9.09, 0.15]
1.5 Heart rate (bpm)	2	166	Mean Difference (IV, Fixed, 95% CI)	0.53 [‐1.76, 2.83]
1.5.1 Absolute values at follow‐up	1	111	Mean Difference (IV, Fixed, 95% CI)	‐0.74 [‐5.17, 3.69]
1.5.2 Change from baseline	1	55	Mean Difference (IV, Fixed, 95% CI)	1.00 [‐1.69, 3.69]
1.6 Systolic blood pressure	2	166	Mean Difference (IV, Fixed, 95% CI)	‐1.62 [‐3.59, 0.36]
1.6.1 Absolute values at follow‐up	1	111	Mean Difference (IV, Fixed, 95% CI)	1.00 [‐4.54, 6.54]
1.6.2 Change from baseline	1	55	Mean Difference (IV, Fixed, 95% CI)	‐2.00 [‐4.11, 0.11]
1.7 Blood oxygen saturation	2	165	Mean Difference (IV, Fixed, 95% CI)	‐0.14 [‐0.59, 0.30]
1.7.1 Absolute values at follow‐up	1	110	Mean Difference (IV, Fixed, 95% CI)	‐0.20 [‐0.72, 0.32]
1.7.2 Change from baseline	1	55	Mean Difference (IV, Fixed, 95% CI)	0.00 [‐0.83, 0.83]
1.8 3‐HPMA (pmol/mg creatinine)	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
1.8.1 Absolute values at follow‐up	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
1.9 NNAL (pmol/mg creatinine))	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
1.9.1 Absolute values at follow‐up	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
1.10 2‐HPMA (pmol/mg creatinine)	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
1.10.1 Absolute values at follow‐up	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
1.11 HMPMA (pmol/mg creatinine)	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
1.11.1 Absolute values at follow‐up	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
1.12 PheT (pmol/mg creatinine)	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
1.12.1 Absolute values at follow‐up	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
1.13 CEMA (pmol/mg creatinine)	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
1.13.1 Absolute values at follow‐up	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
1.14 AAMA (pmol/mg creatinine)	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
1.14.1 Absolute values at follow‐up	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
1.15 FEV1	2		Std. Mean Difference (IV, Fixed, 95% CI)	Totals not selected
1.15.1 Change from baseline	2		Std. Mean Difference (IV, Fixed, 95% CI)	Totals not selected
1.16 FEV1/FVC (%)	2	81	Mean Difference (IV, Fixed, 95% CI)	‐0.16 [‐1.83, 1.50]
1.16.1 Change from baseline	2	81	Mean Difference (IV, Fixed, 95% CI)	‐0.16 [‐1.83, 1.50]
1.17 PEF (L/min)	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
1.17.1 Change from baseline	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
1.18 Product use at 6+ months	5		Risk Ratio (M‐H, Fixed, 95% CI)	Totals not selected