Camarelles 2002.

Methods	Study design: Randomized controlled trial Country: Spain Recruitment: Primary care Group size: 10 ‐ 14
Participants	106 smokers (any amount); 54% women, av. age 47, av. cpd 25 Therapists: 1 doctor, 3 nurses, trained and experienced
Interventions	72 participants eligible for nicotine patch, 53 used 1. Group therapy, 7 x 2 hrs over 3 wks, TQD after wk 3 2. Individual counselling, not matched for intensity, 2 sessions over 2 wks, with S‐H materials
Outcomes	Sustained abstinence at 6 m Validation: none
Notes	Comparison 1.2.2 between group and shorter individual therapy Slightly higher and longer use of NRT in group condition
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Randomized, method not described
Allocation concealment (selection bias)	Unclear risk	Sealed opaque envelopes, but chosen by participant. Since all received a cessation intervention, potential for selection bias probably low
Blinding of outcome assessment (detection bias) All outcomes	Low risk	No biochemical validation but all participants received a cessation intervention
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No information on losses to follow‐up but all participants included in denominators