Comparative effects of behaviour change techniques using eHealth and mHealth in promoting dietary behaviour: protocol for a systematic review and component network meta-analysis.

Introduction: Globally, it is estimated that dietary habits contribute to 22% of adult deaths and 15% of disability-adjusted life years, highlighting the critical role of dietary behaviour in public health. Despite the known benefits of healthy eating, many individuals find it challenging to change their diet for disease prevention. eHealth and mHealth interventions using behaviour change techniques (BCTs) have emerged as promising strategies to address this issue. However, the specific BCTs that are most effective in promoting dietary behaviour are not well established. This systematic review and component network meta-analysis (CNMA) aims to estimate the effect size of each BCT on fostering healthy eating.

Methods And Analysis: We will include randomised controlled trials that assess the effects of eHealth and mHealth interventions on promoting changes in dietary behaviours among healthy adults. Studies with a minimum follow-up period of 3 weeks will be considered. Searches will be conducted in MEDLINE [PubMed], Embase [Dialogue], Cochrane Central Register of Controlled Trials, PsycInfo [Dialogue], ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform and the University Hospital Medical Information Network Clinical Trials Registry on 27 January 2024. Two independent reviewers will conduct title and abstract screening followed by a full-text review. Disagreements will be resolved through discussion or consultation with a third reviewer. The primary outcome is dietary behaviour, as measured by changes in the diet quality score and the intake of a specific food. Our data synthesis will apply a frequentist random-effects model for pairwise meta-analysis, network meta-analysis and an additive CNMA model to compute the effect size of each BCT. This methodological approach will reveal the positive and negative effects of each BCT and provide a ranking of these techniques, considering both direct and indirect evidence.

Ethics And Dissemination: Ethical approval is not required for this systematic review because it uses existing published data. These results will be submitted for publication in a peer-reviewed journal. The current protocol was submitted to PROSPERO on 16 January 2024 (CRD 42024502217).