Cummins 2016b.

Methods	Setting: California USA; pregnant women Recruitment: Callers to University of California San Diego California Smokers' Helpline
Participants	1173 pregnant (< 27 weeks) women, willing to quit within 1 month or recent quitters, av. age 26.3, av. cigs/day 11.2
Interventions	1. Self‐help American Cancer Society's Make Yours a Fresh Start Family fact sheets, and additional tips for quitting while pregnant 2. As 1, plus proactive TC specifically developed for pregnant smokers, including 9 x 30 ‐ 45‐min sessions on days 0, 1, 3, 7, 14, and 30 after quit date, at 32 weeks of gestation, and 2 and 4 weeks after delivery
Outcomes	Abstinence at 6 m post‐partum (180‐day abstinence) Validation: saliva cotinine < 13 ng/mL
Notes	New for 2018 update. Previously listed under studies awaiting assignment as Zhu 2004 Funding: "This research was supported by the Tobacco‐Related Disease Research Program (Grant 8RT‐0103) and First 5 California (Contract CCFC‐6810) and by funds received from the California Department of Health Services Tobacco Control Section (Contract 00–90605)." Declarations of interest: none declared
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Random allocation to condition was done by computer using blocks of 20"
Allocation concealment (selection bias)	Low risk	Quote: "staff were blind to group assignment until the end of the intake, when the appropriate script was presented"
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Abstinence biochemically validated
Incomplete outcome data (attrition bias) All outcomes	Low risk	Higher % lost to follow‐up in intervention arm