Abstract: Health behaviour models typically neglect habitual action. The Self-Report Habit Index (SRHI) permits synthesis of evidence of the influence of habit on behaviour. The purpose of this study is to review evidence around mean habit strength, habit–behaviour correlations, and habit × intention interactions, from applications of the SRHI to dietary, physical activity, and active travel behaviour. Electronic database searches identified 126 potentially relevant papers. Twenty-two papers (21 datasets) passed eligibility screening. Mean scores and correlations were meta-analysed using fixed, random and mixed effects, and interactions were synthesised via narrative review. Twenty-three habit–behaviour correlations and nine habit × intention interaction tests were found. Typical habit strength was located around the SRHI midpoint. Weighted habit–behaviour effects were medium-to-strong (fixed: r + = 0.44; random: r + = 0.46). Eight tests found that habit moderated the intention–behaviour relation. More comprehensive understanding of nutrition and activity behaviours will be achieved by accounting for habitual responses to contextual cues.
Keywords: Habit, SRHI, intention, activity, nutrition