NCT00158158.

Methods	Study design: RCT Location: USA Setting: not reported Recruitment: not reported
Participants	N= 200 Specialist population?: adolescents aged 13 ‐ 19 Participant characteristics: Inclusion criteria: smoke at least 5 cigarettes a day for at least 6 months; does not regularly use other tobacco products; motivated to quit smoking; not currently using medications to quit smoking; willing to use an effective form of contraception throughout the study. Exclusion criteria: NRT is medically inadvisable; diagnosed with a psychiatric disorder within 3 months prior to enrolment; currently taking an unstable dose of psychoactive medications; currently taking medications that may react with a nicotine patch; history of alcohol or drug abuse within 3 months prior to enrolment; pregnant Preference for quitting abruptly versus gradually: not reported
Interventions	All participants asked to make a quit attempt. Those that fail randomised to groups below: Comparator: Usual care: participants asked to set another quit day and quit abruptly Modality of support: not reported Overall contact time: not reported Number of sessions: not reported Pharmacotherapy: nicotine patches Quit date set?: yes Intervention: Smoking reduction: participants advised to reduce smoking rates prior to quit day. Encouraged to decrease smoking by 50% the first week and 75% the second week. During Week 3, participants will be encouraged to completely quit smoking Modality of support: not reported Overall contact time: not reported Number of sessions: not reported Pharmacotherapy: nicotine patches Quit date set?: yes
Outcomes	Definition of abstinence: not reported Longest follow‐up: 6 m Biochemical validation: unclear
Funding source	National Institute on Drug Abuse (NIDA) (NIDA‐14538‐2)
Author conflicts of interest	Not reported
Notes	Relevant comparisons: 1) Reduction versus abrupt We classify this study as included rather than ongoing, as the trial registry lists the study as completed in 2007. However, we have been unable to identify any published data and we did not receive a response to a query to the investigator
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No information provided
Allocation concealment (selection bias)	Unclear risk	No information provided
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No information provided
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No information provided
Other bias	Unclear risk	The study is believed to be completed, but results have not been reported. Insufficient information to judge whether this is as a result of selective reporting