Fraser 2014.

Methods	Setting: USA; population‐based Recruitment: 5‐step process: (1) clicked link to study; (2) completed eligibility screening questions; (3) reviewed consent and confirm willingness to participate; (4) completed baseline questionnaire; (5) call to an automated answering machine to confirm their participation
Participants	1034 smokers of ≥ 5 cigs/day, aged 17 or older, interest in quitting smoking within the next 30 days, 32% M, av. age 39.3, av. cigs/day 19.3
Interventions	Factorial design of the following 5 conditions: website (active/lite), S‐H brochure (full/lite), text messaging, NRT, and proactive TC ‐ 5 sessions of a duration of 30 mins upon enrolment, and 15 mins on quit day or day after, and weekly for 3 weeks
Outcomes	Self‐reported abstinence at 7 m (7‐day PP) Validation: none
Notes	New for 2018 update Funding: "The project was funded through a contract to our university from Matthews Media Group, underwritten by ARRA funding to the National Cancer Institute. Additional funding was provided by the National Cancer Institute (5K05CA139871)." Declarations of interest: none declared
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No detail on exactly how the participants were randomised: Quote: “Randomization occurred immediately after the confirmation call, and participants completing this step were sent an automated email welcoming them to the study and outlining services they would receive (based on their randomization).”
Allocation concealment (selection bias)	Unclear risk	As above
Blinding of outcome assessment (detection bias) All outcomes	High risk	Abstinence not biochemically validated. Level of personal contact differed between arms
Incomplete outcome data (attrition bias) All outcomes	Low risk	Small percentage of lost to follow‐up in each arm