The effect of reduced street lighting on road casualties and crime in England and Wales: controlled interrupted time series analysis

• Published in: Journal of epidemiology and community health (1979) Vol. 69; no. 11; pp. 1118 - 1124
• Main Authors: Steinbach, Rebecca, Perkins, Chloe, Tompson, Lisa, Johnson, Shane, Armstrong, Ben, Green, Judith, Grundy, Chris, Wilkinson, Paul, Edwards, Phil
• Format: Journal Article
• Language: English
• Published: England BMJ Publishing Group Ltd 01.11.2015; BMJ Publishing Group LTD; BMJ Publishing Group
• Subjects: Accidents, Traffic - trends; Adaptation; Carbon; Carbon Footprint - standards; Community; Cost Control; Costs; Crime - trends; Databases, Factual; Emissions; England - epidemiology; Exterior lighting; Heterogeneity; Humans; Interrupted Time Series Analysis; Light emitting diodes; Lighting; Lighting - economics; Lighting - standards; Lighting - trends; Observational studies; Other Topics; Poisson Distribution; Police; Public health; Roads; Roads & highways; Studies; Time series; Wales - epidemiology; England; Wales; United Kingdom > UK; British Isles, England; British Isles, Wales; Environmental epidemiology; ACCIDENTS; SPATIAL ANALYSIS
• ISSN: 0143-005X; 1470-2738
• DOI: 10.1136/jech-2015-206012

BackgroundMany local authorities in England and Wales have reduced street lighting at night to save money and reduce carbon emissions. There is no evidence to date on whether these reductions impact on public health. We quantified the effect of 4 street lighting adaptation strategies (switch off, part-night lighting, dimming and white light) on casualties and crime in England and Wales.MethodsObservational study based on analysis of geographically coded police data on road traffic collisions and crime in 62 local authorities. Conditional Poisson models were used to analyse longitudinal changes in the counts of night-time collisions occurring on affected roads during 2000–2013, and crime within census Middle Super Output Areas during 2010–2013. Effect estimates were adjusted for regional temporal trends in casualties and crime.ResultsThere was no evidence that any street lighting adaptation strategy was associated with a change in collisions at night. There was significant statistical heterogeneity in the effects on crime estimated at police force level. Overall, there was no evidence for an association between the aggregate count of crime and switch off (RR 0.11; 95% CI 0.01 to 2.75) or part-night lighting (RR 0.96; 95% CI 0.86 to 1.06). There was weak evidence for a reduction in the aggregate count of crime and dimming (RR 0.84; 95% CI 0.70 to 1.02) and white light (RR 0.89; 95% CI 0.77 to 1.03).ConclusionsThis study found little evidence of harmful effects of switch off, part-night lighting, dimming, or changes to white light/LEDs on road collisions or crime in England and Wales.