Randomized controlled trial evaluation of a tailored leaflet and SMS text message self-help intervention for pregnant smokers (MiQuit).

INTRODUCTION Study aims were to assess the feasibility and acceptability of a tailored self-help smoking cessation intervention for pregnant smokers (MiQuit). Secondary aims were to assess whether MiQuit affected cognitive determinants of quitting and to provide a range of potential effect sizes of the intervention effect on smoking abstinence. METHODS A randomized controlled trial was undertaken in which pregnant smokers were allocated to either receive MiQuit, a tailored self-help leaflet followed by an 11-week program of tailored text messages, or to a control group, receiving a nontailored self-help leaflet. Participants were 207 pregnant smokers identified by community midwives across 7 NHS Trusts (United Kingdom). At 3-month follow-up, intervention acceptability, cognitive determinants of quitting, and smoking outcomes (self-reported and cotinine-validated 7-day point prevalence abstinence) were assessed. RESULTS Feasibility: 94% (95% CI 89%-99%) of MiQuit participants reported receiving both intervention components. Acceptability: 9% (95% CI 4%-15%) of MiQuit participants opted to discontinue the text messages. Mechanism: compared with controls, MiQuit participants were more likely to set a quit date (p = .049) and reported higher levels of self-efficacy (p = .024), harm beliefs (p = .052), and determination to quit (p = .019). Potential efficacy: self-reported abstinence-MiQuit 22.9%, control 19.6%; odds ratio (OR) = 1.22, 95% CI 0.62-2.41; cotinine-validated abstinence-MiQuit 12.5%, control 7.8%; OR = 1.68, 95% CI 0.66-4.31. CONCLUSIONS Delivering tailored smoking cessation support to pregnant smokers via leaflet and text message is feasible and acceptable. The positive effects of MiQuit on cognitive determinants and the likelihood of setting a quit date are encouraging. A larger efficacy trial is warranted.