Siddiqi 2013.

Methods	BUPROPION Cluster randomized trial Setting: health centres, Pakistan Recruitment: patients from participating health centres with suspected pulmonary tuberculosis
Participants	33 health centres covering 1955 adult smokers with suspected tuberculosis (1299 included in arms relevant to this review), smoking ≥ 1cpd or smoking hookah on a daily basis 95%M, av age 41, av cpd 19 (where one hookah counts as 2 cigarettes)
Interventions	1. 7 weeks bupropion (75mg/d first week, 150mg/d thereafter) 2. No pharmacotherapy Both arms: 2 sessions of brief, in‐person behavioural support (Note, third arm received usual care only, not included in this review)
Outcomes	Continuous abstinence at 6m Validation: CO ≤ 9 ppm
Notes	New for 2013 Reported narratively only due to substantial heterogeneity of program effects across clusters. 275/659 quit intervention vs 254/640 control, adjusted RR 1.1 (0.5–2.3). Funding: International Development Research Centre
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated
Allocation concealment (selection bias)	Low risk	Cluster randomized trial. “A researcher who was blinded to center identity” allocated conditions
Blinding (performance bias and detection bias) All outcomes	High risk	No blinding
Incomplete outcome data (attrition bias) All outcomes	Low risk	No clinics dropped out post‐randomization. Over 90% of participants followed up at 6m
Other bias	High risk	Substantial heterogeneity of program effects across clusters. 20% of participants in control arm smoked only hookah (no cigarettes) compared to 4% in intervention arm.