State laws addressing teen dating violence in US high schools: A difference-in-differences study.

OBJECTIVE: Teen dating violence (TDV) is prevalent with lifelong adverse consequences, and strategies to reduce its burden are needed. Many U.S. states have enacted laws to address TDV in schools, but few studies have examined their effectiveness. This study aimed to assess whether state TDV laws were associated with changes in physical TDV victimization among high school students.

METHODS: We used repeated cross-sectional data of high school students from the Youth Risk Behavior Survey across 41 states from 1999 to 2019. Using a difference-in-differences approach with an event study design, we compared changes in past-year physical TDV in states that enacted TDV laws (n = 21) compared to states with no laws (n = 20). Analyses accounted for clustering at the state-level and state and year-fixed effects. We conducted sensitivity analyses to assess the robustness of our findings.

RESULTS: In our sample of 1,240,211 students, the prevalence of past-year physical TDV was 9.2% across all state-years. In 1999, the prevalence of TDV at the state-level ranged from 7.5 to 13.0%; in 2019, the prevalence ranged from 3.7 to 10.5%. There was no significant association between TDV laws and past-year physical TDV. Six or more waves after enactment, we observed a non-significant 1.7% percentage point reduction in TDV in states with TDV laws (95% CI: -3.6 to 0.3 percentage points; p = 0.10).

CONCLUSIONS: We found no significant association between enactment of TDV laws and physical TDV among high school students. Further research is needed to understand how TDV laws are implemented and components of TDV laws that may influence effectiveness.