Physical inactivity is one of the leading causes for the growing prevalence of non-communicable diseases worldwide and there is a need for more evidence on the effectiveness and cost-effectiveness of interventions that aim to increase physical activity at the population level. This study aimed to update a systematic review published in 2008 by searching peer-reviewed and unpublished literature of economic evaluations of transport interventions that incorporate the health related effects of physical activity. Our analysis of methods for the inclusion of physical activity related health effects into transport appraisal over time demonstrates that methodological progress has been made. Thirtysix studies were included, reflecting an increasing recognition of the importance of incorporating these health effects into transport appraisal. However, significant methodological challenges in the incorporation of wider health benefits into transport appraisal still e xist. The inclusion of physical activity related health effects is currently limited by paucity of evidence on morbidity effects and of more rigorous evidence on the effectiveness of interventions. Significant scope exists for better quality and more transparent reporting. A more consistent approach to the inclusion of benefits and disbenefits would reinforce the synergies between the health, environmental, transport and other sectors. From a transport sector perspective the inclusion of physical activi ty related health benefits positively impacts cost effectiveness, with the potential to contribute to a more efficient allocation of scarce resources based on a more comprehensive range of merits. From a public health perspective the inclusion of physical activity related health benefits may result in the funding of more interventions that promote active transport, with the potential to improve population levels of physical activity and to reduce prevalence of physical activity related diseases.
KeywordsActive transport, economic evaluation, physical activity
IntroductionPhysical inactivity is the fourth leading risk factor for mortality worldwide (1) and is one of the main contributors to the global burden of non-communicable diseases. Physical inactivity increases the risk of many adverse health conditions, including obesity, coronary heart disease, stroke, breast and colon cancer, diabetes, dementia and depression (2-4). Rates of physical inactivity are high worldwide, with technological progress meaning that we now spend less energy in our everyday lives than our predecessors (5, 6). Coupled with the fact that we also have more access to energy dense foods, this constitutes increasingly obesogenic environments requiring ecological solutions (7-9). In order to 2 address the observed low levels of physical activity across populations, it is widely recognised that the incorporation of more incidental physical activity into everyday life is required through environmental, social, cultural and behavioural approaches (10).Active forms of transport, such as...