Improving adherence to web-based cessation programs: a randomized controlled trial study protocol

Amanda L Graham, Sarah Cha, George D Papandonatos, Nathan K Cobb, Aaron Mushro, Ye Fang, Raymond S Niaura, David B Abrams, Amanda L Graham, Sarah Cha, George D Papandonatos, Nathan K Cobb, Aaron Mushro, Ye Fang, Raymond S Niaura, David B Abrams

Abstract

Background: Reducing smoking prevalence is a public health priority that can save more lives and money than almost any other known preventive intervention. Internet interventions have the potential for enormous public health impact given their broad reach and effectiveness. However, most users engage only minimally with even the best designed websites, diminishing their impact due to an insufficient 'dose'. Two approaches to improve adherence to Internet cessation programs are integrating smokers into an online social network and providing free nicotine replacement therapy (NRT). Active participation in online communities is associated with higher rates of cessation. Integrating smokers into an online social network can increase support and may also increase utilization of cessation tools and NRT. Removing barriers to NRT may increase uptake and adherence, and may also increase use of online cessation tools as smokers look for information and support while quitting. The combination of both strategies may exert the most powerful effects on adherence compared to either strategy alone.

Methods/design: This study compares the efficacy of a smoking cessation website (WEB) alone and in conjunction with free NRT and a social network (SN) protocol designed to integrate participants into the online community. Using a 2 (SN, no SN) x 2 (NRT, no NRT) randomized, controlled factorial design with repeated measures at baseline, 3 months, and 9 months, this study will recruit N = 4,000 new members of an internet cessation program and randomize them to: 1) WEB, 2) WEB + SN, 3) WEB + NRT, or 4) WEB + SN + NRT. Hypotheses are that all interventions will outperform WEB and that WEB + SN + NRT will outperform WEB + NRT and WEB + SN on 30-day point prevalence abstinence at 9 months. Exploratory analyses will examine theory-driven hypotheses about the mediators and moderators of outcome.

Discussion: Addressing adherence in internet cessation programs is critical and timely to leverage their potential public health impact. This study is innovative in its use of a social network approach to improve behavioral and pharmacological treatment utilization to improve cessation. This approach is significant for reducing tobacco's devastating disease burden and for optimizing behavior change in other arenas where adherence is just as critical.

Trial registration: ISRCTN:ISRCTN45127327.

Figures

Figure 1
Figure 1
Research model. Theoretical model depicting the intervention components, main outcome variable, and mediating variables.
Figure 2
Figure 2
Study procedures. Flowchart of study procedures from enrollment through follow-up data collection.
Figure 3
Figure 3
Mediational model. Conceptual diagram depicting the intervention (X), outcome (Y), and mediator (Z) variables as well as theory (a), action (b), and outcome (c’) pathways which will be examined in mediational analyses.

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