This synthesis of existing research examined data across 80 studies on the relationship between HVE efforts and safety outcomes, with a focus not buckling up, speeding, and drunk, distracted and aggressive driving. The results indicate that HVE is effective at reducing these risky behaviors, which makes roads safer for everyone using them.
The full report is available here: https://rosap.ntl.bts.gov/view/dot/62379.
Appendices are at https://rosap.ntl.bts.gov/view/dot/62377.
A summary can be found at https://rosap.ntl.bts.gov/view/dot/62378.