Bailey 2013.

Methods	Country: USA Setting: 10 continuation high schools, San Francisco Bay Area Study design: RCT
Participants	Participants: 143 smokers (I = 72, C = 71). 38% female Age: mean = 16.9 years, SD = 0.80 Criteria for inclusion: 14‐18 years old, attended a participating school, smoked ≥ 10 cpd, expressed interest in quitting smoking. Excluded if currently receiving treatment for major depression, panic disorder, social anxiety or agoraphobia; taking antidepressants, antipsychotics, benzodiazepines or theophylline; current heavy alcohol or substance abuse; diagnosed heart problems or high blood pressure; current use of nicotine replacement therapy; allergy to adhesive tape; currently pregnant or planning on becoming pregnant. Follow‐up method: self‐report through questionnaire Inducements to enter study: gift cards, values not reported No differences in baseline participant characteristics between trial arms Pre‐test smoking status assessment: cpd mean = 13.9, SD = 5.53, dependence measured with mFTQ mean = 17.5, SD = 4.5 Post‐test smoking status assessment: self‐reported biochemically validated abstinence
Interventions	Intervention: extended treatment of 24 weeks of group‐based CBT and skills training, concurrent with 9 weeks of nicotine patch therapy. Extended treatment focuses on relapse prevention skills and effective coping plans. Theoretical basis for intervention: CBT (for the non‐pharmacological component of the intervention) Control: 10 weeks of group‐based CBT and skills training, concurrent with 9 weeks of nicotine patch therapy
Outcomes	Measurement: 7‐day PPA Relevant follow‐up periods: 10 weeks and 26 weeks Verification: expired‐air CO < 10 ppm, using a Bedfont Smokerlyzer Loss to follow‐up: at 26 weeks both intervention and control groups lost 18% of participants Adverse events: specific details not given
Notes	New for 2017 update
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"Computer generated randomisation to extended treatment was conducted by the study statistician"
Allocation concealment (selection bias)	Low risk	"Intervention staff and participants remained blind to treatment group assignments until the end of open label treatment"
Blinding of participants and personnel (performance bias) All outcomes	High risk	Behavioural intervention makes blinding difficult, and intervention group received extended treatment in comparison to the control
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Biochemically validated outcome
Incomplete outcome data (attrition bias) All outcomes	Low risk	Loss to follow‐up was 18% in both intervention and control groups, sufficiently low and similar to be judged low risk of attrition bias.