Individual, social and physical environmental correlates of sedentary behaviours in adults: a systematic review protocol

BACKGROUND: Adults spend the majority of their time being sedentary, and evidence suggests that those who spend more of their day engaged in sedentary activities (TV viewing, sitting, screen-based activities) are at increased risk for morbidity and mortality, regardless of whether they exercise regularly. In order to develop effective interventions to reduce sedentary time, it is necessary to identify and understand the strongest modifiable factors of these behaviours. Therefore, the objective of this systematic review is to examine the available evidence in order to identify individual, social, environmental and policy correlates and determinants of sedentary behaviours (TV time, sitting time, screen time) and total sedentary time among adults. METHODS/DESIGN: Six electronic databases will be searched to identify all studies that report on individual, social and/or environmental correlates and determinants of sedentary behaviours and total sedentary time in adults. Grey literature sources including theses, published conference abstracts and websites from relevant organizations will also be included. Articles that report on modifiable individual (e.g. health behaviours and status, self-efficacy, socio-economic status), social (e.g. crime, safety, social support, climate and capital), environmental (e.g. weather, workplace, home, neighbourhood, recreation environment, transportation environment) and policy correlates and determinants (based on study design) of sedentary behaviours in an adult population (mean age ≥18 years) will be included. Study quality and risk of bias will be assessed within and across all included studies. Harvest plots will be used to synthesize results across all correlates, and meta-analyses will be conducted where possible among studies with sufficient homogeneity. DISCUSSION: This review will provide a comprehensive examination of evidence in the field and will serve to highlight gaps for future research on the determinants of sedentary behaviours and inform intervention design. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42014009814