Why we need to view road safety through a public health lens?

Transport poses a public health risk and the burden is greatest on the poorest in society. There is a strong relationship between social class and the likelihood of road traffic injury. In 1980, the Black Report, published by the government department responsible for health in England, identified a strong socioeconomic gradient between child pedestrian fatalities and social class, with children from the lowest social class being five times more likely to die compared to their counterparts the highest social class. The Black Report brought attention to the fact that this did not occur by chance:

While the death of an individual child may appear a random misfortune, the overall distribution indicates the social nature of the phenomenon. (Townsend and Davidson, 1982, p. 127)

Since then further research suggests the relationship between socioeconomic factors and injury persists and has been observed using ecological measures of deprivation for pedestrian casualties, older pedestrians and young drivers.

Identifying such health inequalities and advocating policies to address them is raison d’etre for public health practitioners. However, in the U.K., health inequalities related to road fatalities have not come under the scrutiny of the road safety community largely because the existing database (STATS19) used to inform road safety policy and practice does not routinely collect socioeconomic data. Furthermore, the data variables focused on what “accident” theorists would describe as “active” human errors – at the end of the casual chain. For example, in the case of child pedestrians the event might be described in terms of active errors committed by the collision partners, such as failure of the child to look and see vehicles or the driver speeding or driving whilst impaired. However, little attention was given to upstream latent conditions that gave rise to these events such lack of safe play areas or failure of the local authorities (LAs) to proactively manage safety by implementing measures to reduce speed or enforce speed limits and drink drive legislation.

A public health lens is required to understand the systemic factors that give rise to such inequalities. Dahlgren and Whitehead’s (1991) model of the social determinants of health provides a theoretical lens to understand the social determinants of road casualties by investigating the individual, social, economic and environmental factors that shape people's behaviour and health. The health inequality in road fatalities required an understanding of the latent social, economic and environmental conditions that characterise the risks that children from the lower social classes were exposed to compared to those from more affluent backgrounds.

It took over 10 years from publication of the Black Report for the U.K. Department for Transport (DfT) to commission research to understand the factors that underpinned the startling relationship between pedestrian fatalities and social class. The relationship between socioeconomic status and road casualties is a global one (Ameratunga, Hijar, & Norton, 2006), but it was the U.K. that was at the forefront of taking measures not only to describe but also to tackle this public health problem. The U.K. DfT recognised the need to understand the health inequalities related to road casualties and commissioned a research study to explore the social, economic and environmental factors in child pedestrian accidents (Christie, 1995). This research revealed that a complex interplay of factors predicted child casualties including Victorian gridiron road layouts, through traffic, overcrowding and family structure and higher exposure to risk such as playing in the street and less access to supervised leisure activities. However, whilst all these factors multiply the risks for children from deprived backgrounds, the environmental factors came through strongly as a predictor of casualty group membership.

In the 2002, the government spending review strengthened the national road casualty reduction target by “tackling the significantly higher incidence in disadvantaged communities” (Department for the Environment, Transport and the Region [DETR], 2002) and set up the Neighbourhood Road Safety Initiative (NRSI) as a (World first) demonstration project to reduce the burden of casualties on the poor. Fifteen of the most deprived LAs with the highest child pedestrian casualties in England were allocated funds to develop interventions. LAs were encouraged to identify and treat the latent conditions that gave rise to casualties with targeted interventions and to seek to break road accident causal chains at any number of points. They were also encouraged to include a variety of solutions: a mix of engineering, education, enforcement and health promotion activities. The NRSI evaluation demonstrated that, compared to the control area, the participating area had fewer casualties. The study also revealed the lived experience of “road safety” or lack of it and lives blighted by antisocial behaviour of drivers and moped riders, perceived lack of enforcement, poor quality play areas, lack of affordable leisure activities and cheap reliable public transport (Christie et al., 2010).

National monitoring against casualty targets showed that the rate of decrease was greater in disadvantaged areas compared to more affluent areas (DfT, 2007). Further work has shown that by changing the environment by introducing 20 mph zones – speed limits which are supported by engineering measures to reduce the speed and throughput of vehicle traffic – significantly reduces casualties in deprived areas. The current government has not set road casualty targets. There is no routine monitoring by government of road casualties with respect to social class or ecological measures of deprivation. This is worrying against a background of increasing social inequality (https://www.equalitytrust.org.uk/infographic-income-inequality-uk) and cuts to public services because of austerity measures.

Whilst we should be routinely reviewing casualty data we should also look at the impact of traffic on people's behaviour and the barrier it poses to active travel. Many government policies aim to reduce obesity (which is most prevalent amongst the poor) and encourage active travel (walking and cycling). Such polices will not succeed in improving public health if they are delivered in an environmental context in which people feel unsafe. The research as part of the evaluation of the NRSI revealed that parents felt that the roads were too dangerous for children to walk and cycle and this led to them circumscribing their children's independent mobility and play (Christie et al., 2010). These types of environments have been described as “obesogenic”. As Dorling (2011) argued in his Westminster Lecture “Roads, Casualties and Public Health: The Open Sewers of the 21st Century”:

The deaths that I have been talking about are really only the tip of the problem. The problem extends, of course to non-fatal accidents, to the many major accidents, and the huge number of minor accidents. The problem is also the obesity that's caused and rises because (amongst much else) people don't get out on their trikes at the age of six. It's the timidity that results should you begin to realise how dangerous the environment is outside you. And it's this lack of freedom; taking away the freedom from children; the freedom from other adults; the freedom from older people; the freedom from people on their bikes to travel safely; the freedom for your bus to run on time because there are so many cars.

If we do not address the safety of the environment for everyone and especially the most vulnerable in society, then we will not address health inequalities and may inadvertently increase them. For example, London is promoted as a city where people can cycle and much is being done to address the perceived and actual safety of cycling. However, the dominant demographic of cyclists in London is white, middle class and male – people who arguably have good health and high levels of mobility already (Steinbach, Green, Datta, & Edwards, 2011). Viewing this situation in London, we need to ask which latent conditions give rise to the lack of cycling amongst low social groups, women, older people and children – these groups could be considered as “indicator species” of a safe ecosystem for cycling (Baker, 2009). Fear of injury deters many would-be cyclists, and encourages less sustainable and less active travel mode choices so from a public health perspective we need to know what are the necessary and sufficient conditions to encourage the most vulnerable to see cycling as a safe way to travel.

Health inequalities matter and reducing them makes for a better, fairer society for all. We already know that creating a safer environment can significantly reduce casualties in deprived areas. We also need to understand how creating better environments encourage greater physical activity for health and reduce the burden of non-communicable diseases related to obesity. Unless we routinely monitor and understand health inequalities related to road casualties and barriers to active travel we will not be able to address the latent conditions which give rise to poor health outcomes associated with transport and travelling. We know what works in reducing casualties and from a public health perspective, interventions should be proportionate and universal to address not only the gap between rich and poor but also the gradient that lies between them.