Polosa 2014b.

Study characteristics
Methods	Design: Prospective cohort study Recruitment: Volunteers, leaflets, cessation service kiosk in hospital Setting: Smoking cessation clinic, Italy Study start date: January 2013; Study end date: November 2013
Participants	Total N: 50 Inclusion criteria: Healthy people who smoke 18 – 60 years old Smoking ≥ 15 conventional cpd for at least 10 years Unwilling to quit Exclusion criteria: none stated 40% women, mean age 41, mean cpd 25, mean FTND 6.0 No EC use at baseline, not motivated to quit
Interventions	EC: Refillable 2nd generation devices (personal vaporisers ‐ PVs): EGO/CE4 model, filled with tobacco aroma e‐Liquid containing 9 mg/ml nicotine; instructed to use the study products ad libitum (up to a maximum of 5 ml/day; i.e. half vial) Behavioural support: Participants were instructed how to charge, fill, activate and use the EC. Key troubleshooting was addressed and phone numbers were supplied for assistance. “No emphasis on encouragement, motivation and reward for the smoking cessation‐related efforts were provided during the study.”
Outcomes	4, 8, 12 and 24 wks 30‐day PP verified by CO ≤ 10 ppm Adverse events Cpd, exhaled CO, reduction rates, product usage, and opinions of the EC products
Study funding	"The authors wish to thank FlavourArt (Oleggio, NO, Italy; www.flavourart.it). Authors wish to thank LIAF, Lega Italiana Anti Fumo (Italian acronym for Italian Anti Smoking League) for supporting this research"
Author declarations	"RP has received lecture fees and research funding from Pfizer and GlaxoSmithKline, manufacturers of stop smoking medications. He has also served as a consultant for Pfizer and Arbi Group Srl, an Italian distributor of e‐Cigarettes. RP is currently scientific advisor for LIAF, Lega Italiana Anti Fumo (Italian acronym for Italian Anti Smoking League). PC, MM, JBM, and CR have no relevant competing interest to declare in relation to this work"
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Not controlled
Allocation concealment (selection bias)	High risk	Not controlled
Incomplete outcome data (attrition bias) All outcomes	Low risk	76% followed up, ITT analysis used, no significant differences in baseline characteristics between completers and those lost to follow‐up
Selective reporting (reporting bias)	Unclear risk	Unable to determine prespecified outcomes