Complex interventions to reduce car use and change travel behaviour: An umbrella review.

Abstract

IntroductionCar travel is associated with increased risk of morbidity and mortality, physical inactivity, traffic collisions and casualties, and air and noise pollution. Effective interventions are required to reduce car use and change travel behaviour to sustainable modes. We conducted an umbrella review: 1) determine effective interventions and intervention components to reduce car use and change travel behaviour; and 2) determine where effective components are situated by level of delivery (micro-, meso- or macro-level). MethodsFive databases were searched (2000–2022) for reviews implementing a systematic review process. Data synthesis involved the identification of effective intervention approaches and components and the structuring of components by delivery level. Reviews’ methodological quality was graded. Reviews were assessed for effectiveness (“negative”, “null”, “positive” or “inconclusive”) and consistency of results (“consistent” or “suggestive”). ResultsSearches identified 20,451 records, with 18 included. Eight reviews (moderate quality) were positive consistent (n = 6) or positive suggestive (n = 2) and focused on active school travel (n = 5), walking for transport (n = 1), organisational travel plans (n = 1) and teen mobility (n = 1). One active travel review (workplaces, low quality) was rated positive consistent, with the remaining positive consistent/suggestive reviews having critically low quality: car sharing (n = 1); passive to active travel (n = 1); soft interventions (n = 1); car use reduction (n = 2); and walking school buses (n = 1). Other moderate quality reviews were inconclusive (promotion of walking and cycling (n = 1) and bicycle active school travel (n = 1)) and null consistent (behavioural interventions, n = 1). The majority of effective components were micro-level, with no investigations into intervention cost-effectiveness or inequalities. ConclusionsThis review highlighted evidence to support active school travel, teen mobility, organisational travel plans and walking for transport as effective interventions. When combined, these interventions present a potentially healthy and sustainable life course approach. The majority of effective components were micro-level. More meso- and macro-level, cost-effectiveness and inequality investigations required.