Canga 2000.

Study characteristics
Methods	Design: Randomized controlled trial Setting: 15 primary care centres, 2 hospitals, Spain Recruitment: Identified through practice records
Participants	280 people who smoked with diabetes (incl 16 recent quitters) aged 17 ‐ 84 (133 control, 147 intervention), average age 40.7, 19 cpd, 15% female, did not need to be motivated to quit
Interventions	Intervention: participants received a 40‐minute, face‐to‐face interview on smoking cessation with a nurse and set a quit date. Participants also received self‐help materials. All of those who smoked heavily received nicotine patches unless contraindicated. In addition, participants were provided with a follow‐up program consisting of 5 contacts: a telephone call the day before the quit date, a follow‐up visit 2 weeks after the quit date, a letter 3 weeks after the quit day, a second follow‐up visit 2 months after the quit date, and a final evaluation after 6 months. Control: participants received usual care, established in the Navarre diabetes care program, including advice to quit smoking. No further details reported
Outcomes	> 5m sustained abstinence at 6m Quit attempts Validation: Urine cotinine < 20 ng/ml
Funding Source	Not reported
Author's declarations of interest	Not reported
Notes	Strategy: Adjunctive counseling Level: Patient Comparison type: Single component vs. standard care It is not possible to separate the primary care settings' data from the secondary care settings' data, and so this study is not included in any meta‐analyses
Risk of bias
Bias	Authors' judgement	Support for judgement
Sequence Generation	Low risk	Computer‐generated allocation method
Allocation concealment	Low risk	Sealed envelopes
Blinding of outcome assessors All outcomes	Low risk	Smoking status was validated by urinary cotinine
Incomplete outcome data All outcomes	Low risk	Overall, 0.7% of participants were lost to follow‐up