Environmental, behavioural and multicomponent interventions to reduce adults' sitting time: a systematic review and meta-analysis

Objective To examine the overall effectiveness of interventions for reducing adult sedentary behaviour and to directly compare environmental, behavioural and multicomponent interventions. Design Intervention systematic review with meta-analysis. Data sources Ovid PsycINFO, Ovid MEDLINE, EBSCOHost CINAHL, EBSCOHost SPORTDiscus and PubMed were searched from inception to 26 July 2017. Eligibility criteria Trials including randomised controlled trials, quasi-randomised, cluster-randomised, parallel group, prepost, factorial and crossover trials where the primary aim was to change the sedentary behaviour of healthy adults assessed by self-report (eg, questionnaires, logs) or objective measures (eg, accelerometry). Results Thirty-eight trials of 5983 participants published between 2003 and 2017 were included in the qualitative synthesis; 35 studies were included in the quantitative analysis (meta-analysis). The pooled effect was a significant reduction in daily sitting time of -30.37 min/day (95% CI -40.86 to -19.89) favouring the intervention group. Reductions in sitting time were similar between workplace (-29.96 min/day; 95% CI -44.05 to -15.87) and other settings (-30.47 min/day; 95% CI -44.68 to -16.26), which included community, domestic and recreational environments. Environmental interventions had the largest reduction in daily sitting time (-40.59 min/day; 95% CI -61.65 to -19.53), followed by multicomponent (-35.53 min/day; 95% CI -57.27 to -13.79) and behavioural (-23.87 min/day; 95% CI -37.24 to -10.49) interventions. Conclusion Interventions targeting adult sedentary behaviour reduced daily sitting time by an average of 30 min/day, which was likely clinically meaningful.