Graduation Date

Summer 8-11-2023

Document Type


Degree Name

Doctor of Philosophy (PhD)


Health Services Research, Administration, and Policy

First Advisor

Ronnie Horner

Second Advisor

Hyo Jung Tak

Third Advisor

Fernando Wilson

Fourth Advisor

Lynette Smith, Hongmei Wang


Road traffic crashes are among one of the leading causes of death around the globe. Additionally, it also causes long-term physical disabilities, mental trauma, and financial pressure. By implementing road safety guidelines such as speed limits, drug and alcohol checkpoints, restraints, and penalties, motor vehicle crashes can be reduced. Road traffic crash survival primarily depends on emergency medical service's timely triaging. Rapid triaging and reduced response times can help road traffic crash morbidities and mortalities. However, several factors can be responsible for EMS delays in responding to a fatal crash. This dissertation aims to observe multiple factors related to EMS response times, and driver behaviors before and during the SARS-CoV-2 (COVID-19) pandemic and drill into the effects of cannabis laws across the U.S. and the District of Columbia.

The goal of this dissertation is to look into the effects of county-level socioeconomic factors on the EMS response times during a fatal road traffic crash. Data from the Fatality Analysis Reporting System (FARS) and the Area Health Resource Files for the year 2019 were used for Study 1. For Study 2, 2019 & 2020 FARS data were used to assess driver behaviors before and during the COVID-19 pandemic considering speeding, alcohol & drug use, license status, and duration between the most recent prior crash and the fatal crash. A legal mapping database was created for all laws related to the recreational and medical use of cannabis, cannabis possession decriminalization, and driving while under the influence of alcohol/drug laws. This database allows us to observe a law at one point as of January 28th, 2022, and the ability to study these laws on state law. To demonstrate the Cannabis Legal Mapping database, a proof-of-concept was conducted to assess the effect of THC blood concentration level laws on the detection of cannabinoid presence using a drug test after a fatal crash.

This dissertation underlines road safety issues and recommendations to reduce mortality, improve drivers’ behaviors, and the effects of laws on driver behaviors. When creating laws and health policies, it is vital to consider evidence-based research to design holistic strategies to improve road safety and reduce road traffic crash fatalities.


2023 Copyright, the authors

LM database_07282023_FINAL.xlsx (387 kB)
Cannabis Legal Mapping database

Available for download on Monday, July 29, 2024