Segnan 1991.

Study characteristics
Methods	Design: Randomized controlled trial with 4 active comparators Setting: Primary care practices in Turin, Italy Recruitment: GPs recruited patients opportunistically in practice
Participants	44 providers: GPs with at least 400 individuals on patient list 923 patients: 20 ‐ 60 years of age, currently smoking, no life‐threatening disease. 32.3% F, av. age not reported, av. cpd not reported
Interventions	Common components in all groups: • Physicians attended 2 x 3‐hour training sessions on counseling techniques and organizational aspects of the study Intervention 1: minimal intervention group Participants received 1 session of face‐to‐face counseling and an explanatory brochure Intervention 2: repeated counseling group Participants received 1 session of face‐to‐face counseling, an explanatory brochure and follow‐up appointments at months 1, 3, 6, and 9 (non‐relevant intervention group as GPs provided adjunctive counseling) Intervention 3: nicotine gum group Participants received 1 session of face‐to‐face counseling, an explanatory brochure, follow‐up appointments at months 1, 3, 6, and 9, plus nicotine gum to last until the first follow‐up visit Intervention 4: spirometry group Participants received 1 session of face‐to‐face counseling, an explanatory brochure, follow‐up appointments at months 1, 3, 6, and 9, plus a prescription for spirometry test. Report showed results in the form of lung age
Outcomes	3m prolonged abstinence at 12m Validation: Urinary cotinine < 100 ng/mg Measures of provider implementation: Advise, Arrange
Funding Source	Piedmont Health Authority
Author's declarations of interest	Not reported
Notes	Strategy: Spirometry + Cost‐free medications + Provider training Level: Patient + Provider Type: Active vs active
Risk of bias
Bias	Authors' judgement	Support for judgement
Sequence Generation	Unclear risk	Authors state that a predetermined randomized sequence was used. No further detail provided
Allocation concealment	Low risk	Opaque envelopes were used
Blinding of outcome assessors All outcomes	Low risk	Abstinence was biochemically validated
Incomplete outcome data All outcomes	Unclear risk	The overall loss to follow‐up was 13% at 12 months. No details on the number lost to follow‐up by group were reported