Chengappa 2014.

Study characteristics
Methods	Country: Pittsburgh, USA Setting: 2 outpatient clinics, Western Psychiatric Institute and Clinic; and Dubois Medical Regional Center, Pennsylvania Aim: to assess the efficacy and safety of varenicline to assist in SC among patients with bipolar disorder who were euthymic and motivated to quit smoking Study design: double‐blind placebo‐controlled RCT Dates conducted: February 2010‐March 2013
Participants	60 outpatient smokers with DSM‐IV‐diagnosed bipolar disorder, aged 18‐65, stable state or on medication, willing to quit in the next 30 days, 10+ CPD; randomised to varenicline (31) or placebo (29) Mean age 46, 69% women, 66% white, mean CPD 18.1, mean FTND 6.2 Exclusions: bupropion use (for SC); usual pharmacological criteria
Interventions	Varenicline 1 mg x 2/day, titrated for first week Placebo inactive tablets, same regimen All participants received 15‐min SC counselling at each visit. CO tested and pill counts at each visit. Participants in both groups could reduce the dosage if they wished. TQD was set for week 2 onwards (i.e. full dosage reached) Treatment period was 12 weeks. Weekly pill counts to assess adherence Safety data were reviewed blind monthly by an external independent data safety and monitoring board (DSMB)
Outcomes	Primary: 7‐day PPA, CO‐verified, at 12 weeks Secondary outcomes: 7‐day PPA at 24 weeks; CA at 12, 24 weeks Validation: CO < 10 ppm
Notes	New for 2016 update Study funding: "The National Institute of Mental Health (NIMH) of the NIH, under award R21MH087928 (Dr Chengappa), provided the main funding for this study. Pfizer provided drug/placebo and an investigator‐initiated grant, WS‐515343 (Dr Chengappa). These monies channeled through the University of Pittsburgh were used to offset costs of study procedures, participant payments, and a percentage of the time and effort of research staff and faculty salaries." Author declaration of interests: "Dr Turkin has served on the speaker’s bureau of Forest, Sunovion, and Otsuka; and owns shares of Pfizer stock. Dr George has received investigator‐initiated and contract research support from Pfizer, served as a consultant to Novartis, and received honoraria from National Institutes of Health (NIH) and American College of Neuropsychopharmacology. Drs Chengappa, Perkins, Brar, and Levine, and Mss Schlicht and Hetrick and have no financial disclosures with regards to this study."
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Method not stated, other than "stratified by gender"
Allocation concealment (selection bias)	Unclear risk	Not stated
Blinding (performance bias and detection bias) All outcomes	Low risk	"The treatment assignment was blinded to participating subjects, raters, investigators and statisticians"
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	24 participants in each group completed treatment phase, and 24 (77%) and 20 (69%) completed full study in varenicline and placebo groups respectively Data were analysed using ITT with LOCF
Selective reporting (reporting bias)	Low risk	Prespecified outcomes from trial registry all reported
Other bias	Unclear risk	8 participants (4 in each arm) were on bupropion for depression; 3/15 varenicline quitters and 1/3 placebo quitters were on long‐term bupropion