ABSTRACT
BACKGROUND: Most telephone quitlines provide free nicotine replacement therapy (NRT). An 8-week course is recommended, but few users complete it. Information is needed to help quitlines distribute NRT cost-effectively. DESIGN: Randomised two-group trial. SETTING/PARTICIPANTS: Colorado QuitLine callers who smoked 16-20 cigarettes per day at enrolment and who were eligible for and agreed to receive free NRT. INTERVENTION: Provision of 4-week versus 8-week NRT supply; the 8-week supply was shipped in halves and required participants to request the second half (split-shipment protocol). Enrolment occurred during March 2010-February 2011, follow-up concluded in November 2011, and analysis was performed in 2012. MAIN OUTCOME MEASURES: Point abstinence (7 and 30 day) and prolonged abstinence (6 month) from tobacco use. RESULTS: Overall, 1495 study participants were enrolled and 57.7% completed follow-up. Abstinence rates did not differ significantly between study conditions: 13.8% versus 12.4% in 4-week versus 8-week arms, respectively, (30-day point abstinence, non-respondents treated as smokers). NRT duration was similar in both groups, due in part to purchase of additional patches in the 4-week group. About one-third of the 8-week group requested the full 8-week supply and had higher abstinence rates. Cost per quit was lower in the 4-week (compared to 8-week) group. CONCLUSIONS: A randomised trial did not find worse cessation outcomes among quitline users who received half the minimum recommended course of NRT, but offering the full recommended course using a split-shipment protocol may be reasonably cost-effective and supportive of NRT adherers. TRIAL REGISTRATION NUMBER: NCT01889771.