Policy makers aim to base their decisions on the best evidence available, but in a whirl of lobbying, conflicting advice, commercial marketing masquerading as science, and media simplifications, how can they tell which evidence to trust? Some interests actively seek to mislead them, while in areas such as active travel (i.e., physical activity accrued through walking and cycling for transportation purposes) the published evidence simply may not tell them what they need to know about the health impacts.
Most research into walking and cycling is conducted by transport specialists, without consideration of public health issues and using methodologies that are generally less robust than those used in the health sector. An evidence review carried out in 2007 for the UK National Institute for Health and Clinical Excellence (NICE), looking at physical activity and the environment (not just active travel), found a total of 54 studies worthy of inclusion from a possible 94,172 papers (1).
This should not surprise us – each sector has its own concerns, expertise, technical language, and ways of working – but it is a problem we need to address. In fact, we need to address three main problems:
- A lack of awareness among policy makers in sectors such as planning, transport, development, and communities that they need to include physical activity in their thinking.
- Shortage of high-quality evidence, clearly relevant to policy makers, which they could use as the basis of good policy making.
- Where good physical activity policy does exist, the guidance and advice to professionals working in these sectors on how best to act on it is poor.
The good news, however, is that public health and physical activity specialists do, by and large, understand the importance of active travel, and of making the environment more active travel-friendly. I believe it is important now to convey this understanding to the professionals whose work actually shapes the environment.
Sustrans is a UK-based non-profit organisation (nongovernmental organisation), working on practical projects that encourage and enable more people to travel on foot and by bike more often, to tackle climate change, to reduce pollution, and to improve public health. We also seek to facilitate more effective collaboration between the sectors mentioned above, with a flow of high-quality evidence and best practice information on the health benefits of walking and cycling measures, interpreted into the language of these various groups, and delivered regularly.
GETTING THE MESSAGE ACROSS
It is not safe to assume that the fact something is published – research, good practice studies, or expert guidance – means it will be read and acted upon. More than likely, it will be avidly sought out by those who are already convinced, while the majority of professionals will carry on in sublime ignorance. In the case of active travel this is doubly true: why should we expect a transport planner to scan the public health journals, rank research papers, and decode their sometimes obscure language?
Sustrans has addressed this problem by building a database of over 25,000 individual policy makers and professionals, across all the fields concerned, and providing them with a regular flow of information, on paper and electronically, about public health, disease prevention, physical activity, and active travel. This information is a mixture of project reports and case studies, pointers to the most relevant and robust recent papers, and more intensive and heavily referenced information sheets. It is backed up by an evidence gateway page called The Evidence! (2), which acts as a one-stop bibliography for the best and latest papers.
The database is segmented, in part to ensure that users receive only the information they need, and also because each sector requires appropriate technical language and arguments. Within each sector we identify four "layers" of government and administration, each of which requires a specific approach:
- the authors of national and international policy, who need top-grade reviewed and published evidence, interpreted to make it relevant to their policy objectives;
- the developers of official guidance who interpret policy for professionals in the relevant fields, and may be open to assistance and collaboration;
- professionals such as land use planners, developers, transport planners and architects, who shape the environment but who may be unaware of policy and guidance on how to maximise the positive health impacts of their work; and
- the public – including the members of three groups above in their private lives – who may need convincing that active travel is realistic and valuable.
SYNERGY BETWEEN POLICY AREAS
The UK government seeks to identify the best value in investment decision-making, and where possible to compare the economic impact of different policies and measures. The approach used by NICE to compare healthcare treatments or health promotion approaches is to calculate a cost per Quality Adjusted Life Year (QALY) gained. This will increasingly allow comparisons between different approaches, such as between physical activity interventions and use of statins (drugs that aim to decrease cholesterol) in reducing heart disease risk. If a QALY can be "bought" for less than £20,000 it is considered good value, in NICE terms. This approach seems to me exemplary, even if its perfect transparency means that NICE regularly suffers simplistic media criticism relating to individual cases.
Transport economists have traditionally been rather more subjective, allocating values to things like journey time saved or journey ambiance. Moreover, one of the largest "costs" in the calculation of benefit-to-cost ratios for walking and cycling schemes is loss of tax revenue from motor fuel sales (3)! This type of historic bias clearly skews investment decisions, and we hope to work with transport policy makers and economists to address it. For now, at least in the UK, the Department for Transport is incorporating into its cost–benefit analysis methodology a limited number of health impacts, such as reductions in mortality from certain causes related to increased levels of physical activity. Sustrans is working to support the Department for Transport in this development.
A beauty of active travel projects is that they may score well in economic impact analysis across several different sectors. In 2007, Sustrans ran three randomly selected local walking and cycling projects through the then current version of the Department for Transport cost–benefit mechanism, as test schemes. We found benefit-to-cost ratios ranging between 14.9:1 and 32.5:1, around 10 times the benefit of conventional motor-oriented transport investment (4). This level of economic benefit is important in itself, but of course those three projects also generated beneficial impacts in reduced mortality and morbidity from various other physical and mental illnesses, in climate change emissions reduction, and in reductions in anti-social behaviour, none of which are currently valued in the model.
We aim to work intensively with government on this area in the future, and believe that this type of evidence and economic analysis will be crucial to better policy development in all parts of the world. A key objective for the future will be to calculate the marginal cost per QALY gained through increased walking and cycling as a result of various types of intervention, including environmental changes; in some cases we expect the marginal cost to be negative.
We also feel it is important to weave together some of the research being undertaken now to look at the impact of active travel on climate change and other emissions, physical activity and public health, and the social issues. To this end – and this is a matter of great pride to us – in December 2006 we invited research experts from these fields and from transport to gather and meet, with a view to creating multi-disciplinary research partnerships to study a new programme of local walking and cycling projects. Researchers almost by definition have open minds, and these academics, despite speaking different languages and having quite distinct methodological approaches, quickly established a rapport. We then approached the UK Engineering and Physical Sciences Research Council, which recognised the potential of this type of research partnership and funded a multi-disciplinary research programme combining these areas of research (5).
We aim to continue expanding this inter-sectoral research work in the future, and to intensify the communication programme that informs and motivates those who shape the environment – within which we all live – to make it more actively health-promoting.
References
- National Institute for Health and Clinical Excellence. Promoting and Creating Built or Natural Environments that Encourage and Support Physical Activity. London, UK: NICE; 2007.
- Sustrans. The Evidence! Available at http://www.sustrans.org.uk/default.asp?sID=1091694766555, accessed 1 November 2008.
- Green Alliance and Campaign for Better Transport. Getting Transport Right: Proposals for Better Decision-Making. London, UK: Green Alliance; 2008.
- Sustrans. The National Cycle Network Route User Monitoring Report to End of 2006. Bristol, UK: Sustrans; 2007.
- Engineering and Physical Sciences Research Council. Walking and Cycling: For Sustainable and Healthy Communities. 2007. Available at http://www.epsrc.ac.uk/callsforproposals/archive/walkingandcycling.htm, accessed 4 November 2008.
About the Author
Philip Insall is the Director, Active Travel, Sustrans. Philip comes from a career background in retail distribution and has worked for Sustrans since 1990. He now directs the Active Travel programme of practical physical activity promotion projects, communications, and policy development. Philip has contributed to European policy on health, transport, and climate change, worked with the Department of Health and Department for Transport, with the National Institute for Health and Clinical Excellence on public health guidance development, and in strategic partnership with UK public health network and fora.
