A meta-analysis of studies concerning the safety effects of daytime running lights on cars

  • Published: Accident Analysis and Prevention, 28 (6) 685-694, 1996
  • Authors: Elvik R
  • Date Added: 25 Jan 2014
  • Last Update: 25 Jan 2014
  • Format: html


A meta-analysis of 17 studies that have evaluated the effects on traffic safety of using daytime running lights (DRL) on cars


The studies included in the meta-analysis were retrieved by means of literature surveys that were part of previous evaluation studies and by scanning recent reports. A total of 17 studies were included.

Key Findings:

  • The intrinsic effect of DRL was found to be very robust with respect to both study design and definition of the dependent variable.

  • The best estimate of the intrinsic effect of DRL on cars is a 10-15% reduction in the number of multi-party daytime accidents.


Daytime running lights, Evaluation studies, Meta-analysis, Safety effects


All studies of the aggregate effect of DRL are non-experimental before-and-after studies. This study design does not take account of all confounding factors that are likely to be present.