JMIR Publications

ABSTRACT

Background:

There is a need to deliver smoking cessation support at a population level, both in developed and developing countries. Studies on Internet - and mobile phone based smoking cessation interventions have shown that these methods can be as effective as other methods of support, and they can have a wider reach at a lower cost.

Objective:

The aim of the Randomized Control Trial (RCT), was to compare, on a population level, the efficacy of an identical, tailored smoking cessation intervention delivered by mobile text messaging versus email.

Methods:

We conducted a two-arm, nationwide, double-blinded, fully automated RCT, close to a “real world setting” in Norway. We did not offer incentives to increase participation and adherence, or decrease loss to follow-up. We recruited from users of the website, “slutta.no”, an open, free, multi-component Norwegian Internet-based smoking cessation program, from May 2010 until October 2012. Enrolled smokers were counted as having completed a time point regardless of their response status if it was 1, 3, 6 or 12 months post cessation. We assessed 7315 participants using the following inclusion criteria: knowledge of the Norwegian language, age 16 years or older, ownership of a Norwegian cell phone, having an email account, current cigarette smoker, willingness to set a cessation date within 14 days (mandatory) and completion of a baseline questionnaire for tailoring algorithms. Altogether 6137 participants were eligible for the study and 4378 participants (71.3%) provided informed consent to participate in the smoking cessation trial. We calculated response rates for participants at completed 1, 3, 6 and 12 months post cessation. For each arm, we conducted an intention-to-treat analysis for each completed time point. The main outcome was 7-day self-reported point prevalence abstinence (PPA) at completed six months post cessation. We calculated effect size of the 7-day self-reported PPA in the text message compared with the email arm, as odds ratios (OR) with 95% confidence intervals (CI) for the four time points post cessation.

Results:

At 6 months follow-up, 21.1 % (n=384/1823) in the text message - and 18.6% (n=333/1788) in the email arm responded (P=.07) to the surveys. In an intention-to-treat analyses, 11.5% (n=209/1823) in the text message compared with 11.0% (n=196/1788) in the email arm, (OR =1.05; 95% CI (. 86, 1.30), reported to have achieved 7-days PPA.

Conclusions:

This nationwide, double-blinded, large, fully automated RCT found that 1 in 9 enrolled smokers reported 7-day PPA in both arms, 6 months post cessation. Our study found that identical smoking cessation interventions delivered by mobile text messaging and emails may be equally successful at a population level. Clinical Trial: ClinicalTrials.gov NCT011030427