Hughes 2018.

Study characteristics
Methods	Study design: parallel RCT Country: USA Recruitment: through internet sites, such as Craigslist, and referral by friends already enrolled
Participants	701 smokers: aged ≥ 18 years, ≥ 10 cigarettes per day for ≥ 1 year, probably or definitely intend to quit smoking in the next month, no medical caution to use of patch, no use of other nicotine or tobacco products in the last month 43.5% men; average cigarettes per day: 19; FTND: 5.5; average age started smoking: 17.8; any prior quit attempt: 78%
Interventions	1) Participants advised to 'continue' nicotine patch use in the case of a lapse post‐quit day. Those in the 'continue patch' condition were told: “If you smoke after quitting, continue to use the nicotine patches. Wearing the patches will make it easier for you to return to not smoking. We know that using the patches and smoking a few cigarettes is not harmful. So, if you slip and have a cigarette after quitting, return to not smoking as soon as possible, get rid of any cigarettes you may have, and continue to use the nicotine patches. Do you have any questions or concerns about this?” To minimise adverse events, participants were also told to only use the patch while smoking if they were smoking ≤ 75% of their baseline number of cigarettes per day. 2) Participants advised to 'discontinue' nicotine patch use in the case of a lapse post‐quit day. Those in the 'discontinue patch' condition were told: “If you smoke after quitting, take off your patch for the rest of the day. Using the patches while smoking may give you nicotine levels that are too high, and it's not known if patch use while smoking helps smokers quit. So, if you slip and have a cigarette after quitting, return to not smoking as soon as possible, get rid of any cigarettes you may have, but stop using the patch the day you slip, and resume use on future days only if you completely stop smoking again. Do you have any questions or concerns about this?” For both groups, counsellors delivered the instructions above at least 8 times throughout the interventions, and patches were provided for 10 weeks post‐quit date. For all participants, the behavioural counselling protocol was based on USPHS [United States Public Health Service] Clinical Practice Guidelines that emphasise the provision of social support and problem‐solving around high‐risk‐for‐lapse situations. Counselling was delivered in 6 proactive phone calls that occurred 7 and 3 days before, and 2, 7, 14 and 28 days after participants' designated quit date. The first call lasted about 20 minutes; subsequent calls were 10 to 15 minutes.
Outcomes	Self‐reported 7‐day PPA smoking abstinence at 6 months post‐quit Other abstinence measures: self‐reported 7‐day PPA at 4 months post‐quit Adverse events: measured to 1 week post‐treatment (12 weeks)
Notes	The study was funded by the US National Cancer Institute (Grant CA165080) Conflicts of interest: Dr. Hughes has received consulting and speaking fees from several companies that develop or market pharmacological and behavioral treatments for smoking cessation or harm reduction and from several non‐profit organizations that promote tobacco control. He also consults (without payment) to Swedish Match.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: “The randomization schedule and implementation of randomization was conducted by a statistician who had no contact with participants” Quote: “Treatment condition was based on a stratified block design using the SAS procedure PLAN”
Allocation concealment (selection bias)	Low risk	As above
Blinding (performance bias and detection bias) All outcomes	Low risk	Quote: “Neither participants, research assistants, nor counselors were blind to condition”. However, this is a trial of a behavioural instruction so blinding is impossible. Not biochemically validated, and unknown if participants were aware of the treatment the other group was receiving, but both groups received the same contact. Quote: “We matched the Continue Patch and Discontinue Patch use messages on length and frequency.” Collection of outcomes (detection bias) was blinded as participants completed a survey through a phone line, entering data using the phone keypad.
Incomplete outcome data (attrition bias) All outcomes	Low risk	10% across conditions – reported that this did not differ between groups. 34/321 in 'continue' group did not make a quit attempt and 26/345 in 'discontinue' group ‐ similar between groups