On the buses: a mixed-method evaluation of the impact of free bus travel for young people on the public health

Changing mobility practices. Can meta-ethnography inform transferable and policy-relevant theory?

Social practice theories have attracted attention for their potential insights into how to change transport systems towards "healthier" states. However, most evidence is from small-scale qualitative case studies. We explored whether a synthesis of qualitative evidence on mobility practices in one country, informed by meta-ethnography and a Bourdieusian approach to practice, could produce theory that is of sufficient abstraction to be transferable, yet also capable of informing intervention planning. The synthesis identified three third order constructs: mobility practices result from habitus plus capital in fields; specific configurations of local mobility practices are shaped, but not determined, by material infrastructures and social structures; and changes in practice happen across a number of scales and temporalities. This body of evidence as a whole was then interpreted as an integrative "storyline": Mobility systems are complex, in that outcomes from interventions are neither unilinear nor necessarily predictable from aggregations of individual practice changes. Infrastructure changes may be a necessary, but not sufficient, condition for change. Moving systems towards "healthier" states requires changing habitus such that "healthier" practices align with fields, and that interventions take sufficient account of the power relations that materially and symbolically constrain or enable attachments to and changes in mobility practices. Meta-ethnography is a useful approach for integrating qualitative evidence for informing policy.

Examining the impacts of public transit on healthy aging through a natural experiment: study protocols and lessons learned from the Active El Paso project

This paper describes protocols and experiences from a seven-year natural-experiment study in El Paso, Texas, a border city of predominantly Latino/Hispanic population. The study focuses on how Bus Rapid Transit (BRT) impacts physical activity and thus plays a role in alleviating obesity and related chronic diseases that impact healthy aging. Our protocols describe a longitudinal and case-comparison study, which compared residents exposed to new BRT stations with those who were not. This paper also introduces lessons and experiences to overcome the following challenges: delays in the BRT opening (the main intervention), the COVID-19 pandemic, methodological challenges, participant recruitment and retention, and predatory survey takers. Our transdisciplinary approach was pivotal in addressing these challenges. We also proposed and tested multi-level intervention strategies to reduce modifiable barriers to transit use. Our most important takeaway for researchers, practitioners, and policy makers is the importance of being flexible and ready to adapt to new circumstances. Future natural-experiment researchers need to become more versatile in an increasingly volatile and uncertain world.

Infrastructure, policy and regulatory interventions to increase physical activity to prevent cardiovascular diseases and diabetes: a systematic review

BACKGROUND

Noncommunicable diseases are major contributors to morbidity and mortality worldwide. Modifying the risk factors for these conditions, such as physical inactivity, is thus essential. Addressing the context or circumstances in which physical activity occurs may promote physical activity at a population level. We assessed the effects of infrastructure, policy or regulatory interventions for increasing physical activity.

METHODS

We searched PubMed, Embase and clinicaltrials.gov to identify randomised controlled trials (RCTs), controlled before-after (CBAs) studies, and interrupted time series (ITS) studies assessing population-level infrastructure or policy and regulatory interventions to increase physical activity. We were interested in the effects of these interventions on physical activity, body weight and related measures, blood pressure, and CVD and type 2 diabetes morbidity and mortality, and on other secondary outcomes. Screening and data extraction was done in duplicate, with risk of bias was using an adapted Cochrane risk of bias tool. Due to high levels of heterogeneity, we synthesised the evidence based on effect direction.

RESULTS

We included 33 studies, mostly conducted in high-income countries. Of these, 13 assessed infrastructure changes to green or other spaces to promote physical activity and 18 infrastructure changes to promote active transport. The effects of identified interventions on physical activity, body weight and blood pressure varied across studies (very low certainty evidence); thus, we remain very uncertain about the effects of these interventions. Two studies assessed the effects of policy and regulatory interventions; one provided free access to physical activity facilities and showed that it may have beneficial effects on physical activity (low certainty evidence). The other provided free bus travel for youth, with intervention effects varying across studies (very low certainty evidence).

CONCLUSIONS

Evidence from 33 studies assessing infrastructure, policy and regulatory interventions for increasing physical activity showed varying results. The certainty of the evidence was mostly very low, due to study designs included and inconsistent findings between studies. Despite this drawback, the evidence indicates that providing access to physical activity facilities may be beneficial; however this finding is based on only one study. Implementation of these interventions requires full consideration of contextual factors, especially in low resource settings.

TRIAL REGISTRATION

PROSPERO 2018 CRD42018093429.

Developing and implementing 20-mph speed limits in Edinburgh and Belfast: mixed-methods study

Background

Transport initiatives such as 20-mph (≈30-km/h) speed limits are anticipated to result in fewer road casualties and improve perceptions of safety, leading to increases in active travel. Lower speeds may also lead to more pleasant environments in which to live, work and play.

Objectives

The main objective was to evaluate and understand the processes and effects of developing and implementing 20-mph speed limits in Edinburgh and Belfast. The focus was on health-related outcomes (casualties and active travel) that may lead to public health improvements. An additional objective was to investigate the political and policy factors (conditions) that led to the decision to introduce the new speed limits.

Design

This was a mixed-methods study that comprised an outcome, process, policy and economic evaluation of two natural experiments.

Setting

The study was set in Edinburgh, Scotland, and Belfast, Northern Ireland, from 2000 to 2018.

Participants

The whole population of each city were participants, as well as stakeholders involved in implementation and decision-making processes.

Intervention

The intervention was the implementation of 20-mph legislation, signage, enforcement, and education and awareness-raising in Edinburgh (citywide) and Belfast (city centre).

Main outcome measures

The main outcomes measured were speed; number, type and severity of road collisions; perceptions; and liveability.

Data sources

The following data sources were used – routinely and locally collected quantitative data for speed, volume of traffic, casualties and collisions, and costs; documents and print media; surveys; interviews and focus groups; and Google Street View (Google Inc., Mountain View, CA, USA).

Results

Collisions and casualties – the overall percentage reduction in casualty rates was 39% (the overall percentage reduction in collision rates was 40%) in Edinburgh. The percentage reduction for each level of severity was 23% for fatal casualties, 33% for serious casualties and 37% for minor casualties. In Belfast there was a 2% reduction in casualties, reflecting differences in the size, reach and implementation of the two schemes. Perceptions – in Edinburgh there was an increase in two factors (support for 20 mph and rule-following after implementation) supported by the qualitative data. Liveability – for both cities, there was a small statistical increase in liveability. Speed – mean and median speeds reduced by 1.34 mph and 0.47 mph, respectively, at 12 months in Edinburgh, with no statistically significant changes in Belfast. History, political context, local policy goals, local priorities and leadership influenced decision-making and implementation in the two cities.

Limitations

There was no analysis of active travel outcomes because the available data were not suitable.

Conclusions

The pre-implementation period is important. It helps frame public and political attitudes. The scale of implementation and additional activities in the two cities had a bearing on the impacts. The citywide approach adopted by Edinburgh was effective in reducing speeds and positively affected a range of public health outcomes. The city-centre approach in Belfast (where speeds were already low) was less effective. However, the main outcome of these schemes was a reduction in road casualties at all levels of severity.

Future work

Future work should develop a statistical approach to public health interventions that incorporates variables from multiple outcomes. In this study, each outcome was analysed independently of each other. Furthermore, population measures of active travel that can be administered simply, inexpensively and at scale should be developed.

Study registration

This study is registered as ISRCTN10200526.

Funding

This project was funded by the National Institute for Health and Care Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 10, No. 9. See the NIHR Journals Library website for further project information.

Use of natural experimental studies to evaluate 20mph speed limits in two major UK cities

INTRODUCTION

Reductions in traffic speed can potentially offer multiple health and public health benefits. In 2016, implementation of 20mph (30kph) speed limit interventions began in Edinburgh (city-wide) and Belfast (city centre). The aims of this paper are to describe 1) the broad theoretical approach and design of two natural experimental studies to evaluate the 20mph speed limits in Edinburgh and Belfast and 2) how these studies allowed us to test and explore theoretical mechanisms of 20mph speed limit interventions.

METHODS

The evaluation consisted of several work packages, each with different research foci, including the political decision-making processes that led to the schemes, their implementation processes, outcomes (including traffic speed, perceptions of safety, and casualties) and cost effectiveness. We used a combination of routinely and locally collected quantitative data and primary quantitative and qualitative data.

RESULTS

The evaluation identified many contextual factors influencing the likelihood of 20mph speed limits reaching the political agenda. There were substantial differences between the two sites in several aspects related to implementation. Reductions in speed resulted in significant reductions in collisions and casualties, particularly in Edinburgh, which had higher average speed at baseline. The monetary value of collisions and casualties prevented are likely to exceed the costs of the intervention and thus the overall balance of costs and benefits is likely to be favourable.

CONCLUSIONS

Innovative study designs, including natural experiments, are important for assessing the impact of 'real world' public health interventions. Using multiple methods, this project enabled a deeper understanding of not only the effects of the intervention but the factors that explain how and why the intervention and the effects did or did not occur. Importantly it has shown that 20mph speed limits can lead to reductions in speed, collisions and casualties, and are therefore an effective public health intervention.

Promoting Sustainable Mobility: A Perspective from Car and Public Transport Users

Sustainable mobility is becoming a key factor in improving the quality of life of the residents and increasing physical activity (PA) levels. The current situation of sustainable mobility and its analysis is a first step in understanding the factors that would encourage residents to discover and choose alternative modes of travel. The present study examined the factors that encourage the choice of active modes of travel among urban adult population. Walking and cycling were analyzed as the most sustainable forms of urban mobility from the perspective of car and public transport (PT) users. Total of 902 subjects aged 18 years or older were analyzed in the study to assess commuting habits in Kaunas city, Lithuania. The majority (61.1%) of the respondents used a passenger vehicle, 28.2% used PT, and only 13.5% used active modes of travel. The results showed that safer pedestrian crossings, and comfortable paths were the most significant factors that encourage walking. A wider cycling network, and bicycle safety were the most important incentives for the promotion of cycling. Our findings show that the main factors encouraging walking and cycling among car and PT users are similar, however, the individual characteristics that determine the choice of these factors vary significantly.

Taking the bus? Barriers and facilitators for adolescent use of public buses to school

Transport to school can contribute significantly to adolescents' physical activity but in New Zealand - as in many other countries around the world - many adolescents are driven to school. Public transport offers an opportunity to integrate incidental active transport into school commutes. In this paper, we bring together multiple sources of data into a multi-method study to elucidate the barriers to and facilitators of public transport use by adolescents for school travel in Dunedin, New Zealand, a city with low rates of public transport use. The data include a public bus survey from Otago School Students Lifestyle Survey (OSSLS, 1391 adolescents); the Built Environment Active Transport to School (BEATS) Study parental survey (350 parents), focus groups (54 adolescents, 25 parents, 12 teachers) and semi-structured interviews (12 principals); interviews with three policy-makers from local/regional/national agencies; and analysis of 10 relevant local/regional/national strategies/transport plans. The findings show how distance to school, cost, parental trip chaining, built environment features, the weather, convenience, and safety perceptions are major barriers to using public transport to school. Moreover, current transport planning documents do not favour public health. A number of recommendations that could increase public transport use are made including: raising parking prices to discourage parents driving and trip-chaining; improving bus infrastructure and services; providing subsidies; and changing perceptions of public transport use and users. These actions, however, require collaboration between government authorities across the local, regional and national scale.

Does free public transit increase physical activity and independent mobility in children? Study protocol for comparing children's activity between two Finnish towns with and without free public transit

BACKGROUND

Children's habitual physical activity, including active travel and catching public transit (walking and cycling to and from destinations), and independent mobility (mobility without an adult) have decreased. Public transit trips are physically active and can provide access to hobbies independent of parents, but there is no device-measured data about children's total physical activity time following the introduction of free public transit. Our aim is to compare physical activity and independent mobility between children living in two Finnish towns, one with a recently introduced free public transit system, and the other without free public transit.

METHODS

The city of Mikkeli has provided free public transit for all comprehensive school children since 2017. Various districts from Mikkeli, and the reference town of Kouvola (towns from South-Eastern Finland with a comparative population size and geographical structure), are selected based on their accessibility and the availability of public transit services. Samples of 10-12-year-old children will be recruited through primary schools. We will compare moderate-to-vigorous physical activity time, sitting time (a thigh-worn Fibion® device) and independent mobility (a participatory mapping method, PPGIS) of children: 1) who live in towns with and without free public transit, 2) who live and go to school in districts with high vs. low perceived and objective access to free public transit, and 3) who report using vs. not using free public transit. In addition, ethnography will be used to get insights on the social and cultural effects of the free public transit on children's and parent's everyday life.

DISCUSSION

There is a need for scalable solutions that can increase children's physical activity independent of their socioeconomic background or place of residence. This project will give information on how a political action to provide free public transit for children is associated with their total physical activity time and independent mobility patterns, therefore providing highly relevant information for political decision-making and for promoting independent physical activity in children.

Longitudinal associations between perceptions of the neighbourhood environment and physical activity in adolescents: evidence from the Olympic Regeneration in East London (ORiEL) study

BACKGROUND

Most UK adolescents do not achieve recommended levels of physical activity. Previous studies suggested that perceptions of the neighbourhood environment could contribute to explain differences in physical activity behaviours. We aimed to examine whether five measures of perceptions - perceived bus stop proximity, traffic safety, street connectivity, enjoyment of the neighbourhood for walking/cycling, and personal safety - were longitudinally associated with common forms of physical activity, namely walking to school, walking for leisure, and a composite measure of outdoor physical activity. We further aimed to investigate the moderating role of gender.

METHODS

We used longitudinal data from the Olympic Regeneration in East London (ORiEL) study, a prospective cohort study. In 2012, 3106 adolescents aged 11 to 12 were recruited from 25 schools in 4 deprived boroughs of East London. Adolescents were followed-up in 2013 and 2014. The final sample includes 2260 adolescents surveyed at three occasions. We estimated logistic regression models using Generalised Estimating Equations to test the plausibility of hypotheses on the nature of the longitudinal associations (general association, cumulative effect, co-varying trajectories), adjusting for potential confounders. Item non-response was handled using multiple imputation.

RESULTS

Longitudinal analyses indicate little evidence that perceptions of the neighbourhood are important predictors of younger adolescent physical activity. There was weak evidence that greater perceived proximity to bus stops is associated with a small decrease in the probability of walking for leisure. Results also indicate that poorer perception of personal safety decreases the probability of walking for leisure. There was some indication that better perception of street connectivity is associated with more outdoor physical activity. Finally, we found very little evidence that the associations between perceptions of the neighbourhood and physical activity differed by gender.

CONCLUSIONS

This study suggests that younger adolescents' perceptions of their neighbourhood environment, and changes in these perceptions, did not consistently predict physical activity in a deprived and ethnically diverse urban population. Future studies should use situation-specific measures of the neighbourhood environment and physical activity to better capture the hypothesised processes and explore the relative roles of the objective environment, parental and adolescents' perceptions in examining differences in types of physical activity.

Gender and active travel: a qualitative data synthesis informed by machine learning

BACKGROUND

Innovative approaches are required to move beyond individual approaches to behaviour change and develop more appropriate insights for the complex challenge of increasing population levels of activity. Recent research has drawn on social practice theory to describe the recursive and relational character of active living but to date most evidence is limited to small-scale qualitative research studies. To 'upscale' insights from individual contexts, we pooled data from five qualitative studies and used machine learning software to explore gendered patterns in the context of active travel.

METHODS

We drew on 280 transcripts from five research projects conducted in the UK, including studies of a range of populations, travel modes and settings, to conduct unsupervised 'topic modelling analysis'. Text analytics software, Leximancer, was used in the first phase of the analysis to produce inter-topic distance maps to illustrate inter-related 'concepts'. The outputs from this first phase guided a second researcher-led interpretive analysis of text excerpts to infer meaning from the computer-generated outputs.

RESULTS

Guided by social practice theory, we identified 'interrelated' and 'relating' practices across the pooled datasets. For this study we particularly focused on respondents' commutes, travelling to and from work, and on differentiated experiences by gender. Women largely described their commute as multifunctional journeys that included the school run or shopping, whereas men described relatively linear journeys from A to B but highlighted 'relating' practices resulting from or due to their choice of commute mode or journey such as showering or relaxing. Secondly, we identify a difference in discourses about practices across the included datasets. Women spoke more about 'subjective', internal feelings of safety ('I feel unsafe'), whereas men spoke more about external conditions ('it is a dangerous road').

CONCLUSION

This rare application of machine learning to qualitative social science research has helped to identify potentially important differences in co-occurrence of practices and discourses about practice between men's and women's accounts of travel across diverse contexts. These findings can inform future research and policy decisions for promoting travel-related social practices associated with increased physical activity that are appropriate across genders.

What works to promote walking at the population level? A systematic review

OBJECTIVE

Interventions to promote walking have focused on individual or group-based approaches, often via the randomised controlled trial design. Walking can also be promoted using population health approaches. We systematically reviewed the effectiveness of population approaches to promote walking among individuals and populations.

DESIGN

A systematic review.

DATA SOURCES

10 electronic databases searched from January 1990 to March 2017.

ELIGIBILITY CRITERIA

Eligibility criteria include pre-experimental and postexperimental studies of the effects of population interventions to change walking, and the effects must have been compared with a 'no intervention', or comparison group/area/population, or variation in exposure; duration of ≥12 months of follow up; participants in free-living populations; and English-language articles.

RESULTS

12 studies were identified from mostly urban high-income countries (one focusing on using tax, incentivising the loss of parking spaces; and one using policy only, permitting off-leash dogs in city parks). Five studies used mass media with either environment (n=2) or community (n=3) approaches. Four studies used environmental changes that were combined with policies. One study had scaled up school-based approaches to promote safe routes to schools. We found mass media, community initiatives and environmental change approaches increased walking (range from 9 to 75 min/week).

Physical activity and the environment: conceptual review and framework for intervention research

Background

Changing the physical environment is one way to promote physical activity and improve health, but evidence on intervention effectiveness is mixed. The theoretical perspectives and conceptual issues discussed or used in evaluative studies and related literature may contribute to these inconsistencies. We aimed to advance the intervention research agenda by systematically searching for and synthesising the literature pertaining to these wider conceptual issues.

Methods

We searched for editorials, commentaries, reviews, or primary qualitative or quantitative studies in multiple disciplines by electronic searches of key databases (MEDLINE and MEDLINE In-Process, Web of Science, Cochrane Reviews, ProQuest for dissertations, Health Evidence, EPPI-Centre, TRID and NICE) and snowballing. We extracted theoretical and conceptual material and used thematic analysis in an in-depth, configurative narrative approach to synthesis.

Results

Our initial searches identified 2760 potential sources from fields including public health, sociology, behavioural science and transport, of which 104 were included. By first separating out and then drawing together this material, we produced a synthesis that identified five high-level conceptual themes: one concerning outcomes (physical activity as a behaviour and a socially embedded practice), one concerning exposures (environmental interventions as structural changes) and three concerning how interventions bring about their effects (the importance of social and physical context; (un) observable mechanisms linking interventions and changes in physical activity; and interventions as events in complex systems). These themes are inter-related but have rarely been considered together in the disparate literatures. Drawing on these insights, we present a more generalisable way of thinking about how environmental interventions work which could be used in future evaluation studies.

Conclusions

Environmental and policy interventions are socially embedded and operate within a system. Evaluators should acknowledge this, and the philosophical perspective taken in their evaluation. Across disciplinary fields, future studies should seek to understand how interventions work through considering these systems, the context in which interventions take place, and the (un) observable mechanisms that may operate. This will help ensure that findings can be more easily interpreted and widely applied by policymakers. We hope that highlighting these conceptual issues will help others to interpret and improve upon a somewhat contested evidence base.

Electronic supplementary material

The online version of this article (doi: 10.1186/s12966-017-0610-z) contains supplementary material, which is available to authorized users.

Health impacts of the Cambridgeshire Guided Busway: a natural experimental study

Background

Improving transport infrastructure to support walking and cycling on the journey to and from work – active commuting – could help to promote physical activity and improve population health.

Aims

To assess whether or not investment in new high-quality transport infrastructure was associated with an increase in active commuting; wider health impacts of changes in travel behaviour; determinants of the use and uptake of active commuting; and how changes in travel behaviour were distributed in the population and related to the wider social context.

Design

The Commuting and Health in Cambridge study, comprising a quasi-experimental cohort study combined with both nested and supplementary in-depth quantitative and qualitative studies.

Setting

Cambridgeshire, UK.

Participants

A cohort of 1143 adults living within 30 km of Cambridge, working in the city and recruited in 2009; and a separate sample of 1710 users intercepted on the Cambridgeshire Guided Busway in 2012.

Intervention

The Cambridgeshire Guided Busway, comprising a new bus network using 22 km of guideway (segregated bus track) accompanied by a traffic-free path for pedestrians and cyclists, opened in 2011.

Main outcome measure

Change in time spent in active commuting from 2009 to 2012, using a self-reported measure validated using georeferenced combined heart rate and movement sensor data.

Methods

A delay from 2009 to 2011 in completing the intervention entailed some changes to the original design and attrition of the cohort. A period of methodological and observational research on active commuting preceded the evaluation, which was based on a quasi-experimental cohort analysis together with the intercept and qualitative data. A graded measure of each participant’s exposure to the intervention, based on the proximity of the busway to his or her home, served as the basis for controlled comparisons.

Results

Commuting practices were complex and shaped by various changeable social and environmental factors. Walking and cycling were often incorporated into longer commuting journeys made predominantly by car or public transport. In multivariable multinomial regression analyses, exposure to the intervention was associated with a greater likelihood of a large increase in the proportion of commuting trips involving any active travel [adjusted relative risk ratio (RRR) 1.80, 95% confidence interval (CI) 1.27 to 2.55], of a large decrease in the proportion of trips made entirely by car (RRR 2.09, 95% CI 1.35 to 3.21), and of an increase in weekly cycle commuting time (RRR 1.34, 95% CI 1.03 to 1.76). There was a mixed pattern of effects at the individual level, with the intervention providing a more supportive environment for active commuting for some and not for others. There was some evidence that the effect was most pronounced among those who reported no active commuting at baseline, and observational evidence suggesting a relationship between active commuting, greater overall physical activity, and improved well-being and weight status.

Conclusions

These findings provide new empirical support and direction for reconfiguring transport systems to improve population health and reduce health inequalities. They should be combined with evidence from research evaluating related environmental changes in other settings, preferably using longer periods of observation and controlled comparisons, to support more generalisable causal inference.

Funding

The National Institute for Health Research Public Health Research programme.

What is the effect of reduced street lighting on crime and road traffic injuries at night? A mixed-methods study

Background

Some local authorities have reduced street lighting at night to save energy, but little is known about impacts on public health or about public concerns about impacts on well-being.

Aim

To evaluate the effect of reduced street lighting on crime and road traffic injuries.

Design

A mixed-methods study comprising a rapid appraisal, a controlled interrupted time series analysis and a cost–benefit analysis (CBA).

Setting

England and Wales.

Target population

Residents and workers in eight case study areas; road traffic casualties and victims of crime.

Interventions evaluated

Switch-off (i.e. lights permanently turned off), part-night lighting (e.g. lights switched off between 12 a.m. and 6 a.m.), dimming lights and white lights/light-emitting diodes (LEDs).

Outcomes

Public views about implications on well-being; road traffic injury data (STATS19:http://data.gov.uk/dataset/road-accidents-safety-data) obtained for the period 2000–13; crime data (Police.uk:data.police.uk) obtained for the period December 2010–December 2013. Detailed crime data were obtained from one police force for a methodological study of the spatial level at which Police.uk data are valid for analysis.

Statistical methods

Road traffic collisions were analysed at street segment level. Regression models were used to estimate changes in daytime and night-time collision rates associated with lighting interventions. The ratio of night-time and daytime changes was considered the best estimate of change in night-time collisions following each lighting intervention. Police.uk crime data were found to be reliable when analysed at middle super output area (MSOA) level. For crime, the analysis used the proportion of total km of road in each MSOA with each lighting intervention. Regression models controlled for yearly and monthly trends and were fitted in each geographical region and police force. Effect estimates were pooled in random-effects meta-analyses.

Results

Public concerns centred on personal security, road safety, crime, fear of crime, sleep quality and being able to see the night sky. Street lighting reductions went largely unnoticed or had only marginal impacts on well-being, but for a minority of people switch-off and part-night lighting elicited concerns about fear of the dark, modernity and local governance. Street lighting data were obtained from 62 local authorities. There was no evidence that reduced street lighting was associated with road traffic collisions at night. There was significant heterogeneity in the estimated effects on crime at police force level. Overall, there was no evidence that reduced street lighting was associated with crime. There was weak evidence for a reduction in crime associated with dimming [rate ratio (RR) 0.84, 95% confidence interval (CI) 0.70 to 1.02] and white light (RR 0.89, 95% CI 0.77 to 1.03). The CBA suggests that part-night lighting may represent a net benefit to local authorities.

Limitations

The study did not account for the impacts of other safety/crime prevention initiatives (e.g. improved road markings; closed-circuit television), and so associations may be partly attributable to these initiatives. The CBA was unable to include potentially important impacts such as fear of crime and reduced mobility.

Conclusion

This study found little evidence of harmful effects of switch-off, part-night lighting, dimming or changes to white light/LEDs on levels of road traffic collisions or crime in England and Wales. However, the public were also concerned about other health outcomes. Research is needed to understand how lighting affects opportunities for crime prevention and how these vary by context. Research is needed also on other public health impacts of light at night.

Funding

The National Institute for Health Research Public Health Research programme.