Background Numerous empirical studies provide evidence that roadside sobriety checkpoints reduce alcohol-impaired driving. However, checkpoints are resource-intensive for municipal police departments to conduct. The aims of this study were (1) to examine associations between checkpoint configuration and alcohol-related motor vehicle crashes, and (2) and to explore opportunities to optimize this high-impact intervention.

Method We conducted a series of longitudinal spatial analyses using data for sobriety checkpoints and alcohol-involved motor vehicle crashes in Los Angeles, USA; Brisbane, Australia; and rural Queensland, Australia. Time series and spatial ecological analyses examined associations between checkpoints and crash incidence while accounting for space-time data structures and time-varying confounders (e.g., temperature, precipitation). Additional analyses considered impacts of checkpoint size (the number of officers present) and duration.

Results In Los Angeles, Brisbane and rural Queensland, sobriety checkpoints were associated with fewer alcohol-involved motor vehicle crashes. Relationships were detectable for approximately one week and over geographic areas encompassing approximately 60,000 residents. Checkpoint size and duration did not modify this association.

Conclusions Sobriety checkpoint programs could be optimized. Conducting more frequent checkpoints staffed with fewer police officers will maximize public health impacts and minimize operational costs.

Learning Outcomes

1. To understand that sobriety checkpoints are a high-impact intervention to reduce alcohol-involved motor vehicle crash incidence.

2. To critique spatial epidemiologic methods to examine longitudinal associations between sobriety checkpoints and motor vehicle crashes.

3. To learn opportunities to optimally configure sobriety checkpoint programs to maximize public health benefits and minimize operational costs.