Aims: To assess the long-term efficacy of a fully automated digital multi-media smoking cessation intervention.
Design: Two-arm randomized control trial (RCT). Setting World Wide Web (WWW) study based in Norway.
Participants: Subjects (n = 396) were recruited via internet advertisements and assigned randomly to conditions. Inclusion criteria were willingness to quit smoking and being aged 18 years or older.
Intervention: The treatment group received the internet- and cell-phone-based Happy Ending intervention. The intervention programme lasted 54 weeks and consisted of more than 400 contacts by e-mail, web-pages, interactive voice response (IVR) and short message service (SMS) technology. The control group received a self-help booklet. Additionally, both groups were offered free nicotine replacement therapy (NRT).
Measurements: Abstinence was defined as 'not even a puff of smoke, for the last 7 days', and assessed by means of internet surveys or telephone interviews. The main outcome was repeated point abstinence at 1, 3, 6 and 12 months following cessation.
Findings: Participants in the treatment group reported clinically and statistically significantly higher repeated point abstinence rates than control participants [22.3% versus 13.1%; odds ratio (OR) = 1.91, 95% confidence interval (CI): 1.12-3.26, P = 0.02; intent-to-treat). Improved adherence to NRT and a higher level of post-cessation self-efficacy were observed in the treatment group compared with the control group.
Conclusions: As the first RCT documenting the long-term treatment effects of such an intervention, this study adds to the promise of digital media in supporting behaviour change.