Sadr Azodi 2009.

Methods	Setting: Pre‐surgical clinics, 3 hospitals, Sweden Recruitment: Smokers due to undergo elective surgery for primary hernia repair, laparoscopic cholecystectomy or hip or knee prosthesis. Not selected for motivation to quit, but unwillingness to quit smoking a major reason for refusal to enrol
Participants	117 smokers; 47% F, av. age 55, av. cpd 15; no information about baseline motivation Provider: trained nurse counsellor
Interventions	Intervention: weekly counselling 4 wks pre‐ to 4 wks post‐op, face‐to‐face or by telephone, free choice of NRT product, Control: Standard care
Outcomes	Abstinence at 12m. Post operative complications were primary trial outcomes Validation: CO ≤10 ppm at 2‐3 weeks post op, no validation at 12m
Notes	Smoking cessation was validated by CO in exhaled air.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Stratified block randomization
Allocation concealment (selection bias)	Low risk	Opaque sealed envelopes
Incomplete outcome data (attrition bias) All outcomes	Low risk	7/55 (13%) I 10/62 (16%) C lost to 12‐month follow‐up, treated as smokers