Blebil 2014

Methods	Setting: quit smoking clinics, Malaysia Recruitment: eligible clinic attendees
Participants	231 smokers, 120 in phone support arm and 111 in control 96.1% male, average age: 48, average cigarettes/day: 14
Interventions	1. Relapse prevention: as control with an additional phone call after each visit in month 1 providing information, encouragement, etc. 2. Control: attend quit smoking clinic 4 times in month 1, 2 times in month 2 with a phone call after each visit, and 1 visit with 2 phone calls in month 3, self‐help materials throughout
Outcomes	Point prevalence abstinence at 6 months Validation: CO ≥ 7 ppm at 6 months
Notes	Dropouts counted as continuing smokers Funding not declared Declaration of Interests: "The authors declare that they have no competing interests."
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Assignments created by Urn design
Allocation concealment (selection bias)	Unclear risk	No information on concealment
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	No information on blinding
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Biochemically validated abstinence
Incomplete outcome data (attrition bias) All outcomes	Low risk	Low dropout rate at 6 months