Linking Crash and Post-Crash Data

R12: Linking Crash and Post-Crash Data

Research Team

Prinicipal Investigator
David R. Ragland
University of California, Berkeley

Chris Cherry
University of Tennessee, Knoxville

Funding Organization

Collaborative Sciences Center for Road Safety (CSCRS)


This project addresses two different but important issues in California. One is to provide a more accurate picture of traffic injuries in California by utilizing medical data to fill in where police crash reports may not capture a crash or may have limited information. In this case two immediate applications are to obtain a better estimate of pedestrian and bicyclist injury and a better estimate of traffic injury on tribal areas.

The second is to get a more accurate picture of emergency medical services (EMS) response times as these may be impacted by crash location, EMS response team locations, emergency department (ED) and trauma center locations, communication access, etc. Based on this information we intend to develop a model of EMS response for California that can target variables that can be modified to reduce time between a traffic crash and medical treatment at an ED or trauma center.

This project continues the work of the 2017 CSCRS project “Completing the Picture of Traffic Injuries: Understanding Data Needs and Opportunities for Road Safety.” 

Exhibit 2 showing datasets described in the report

Exhibit 2: Datasets Described in the Report

Following are steps to start in 2018:

  1. Comparing crash and medical data to evaluate “under-reporting” in crash reports: Starting in 2018 we will utilize data provided through Crash Medical Outcomes Data (CMOD) to evaluate the degree to which crash data (i.e., police crash reports) under-report crash injuries. One focus of analyses will be on pedestrian/bicyclist injury, identifying factors (e.g., age, ethnicity, and geographic area) associated with level of reporting. Existing reports suggest that many pedestrian and bicyclist injuries may be missed in crash reports, and we would like to develop estimates of this for the State of California.
  2. Developing measures of EMS response times as a function of rural versus urban, cell phone coverage, trauma center location: We will request data as needed and conduct extensive analyses to determine the time elements between the various events in EMS response as a function of crash location, ED or trauma center location, communication coverage, dispatch policy, etc. The time elements, as listed in the NEMSIS Uniform Pre-Hospital EMS Dataset, include a series of times from the initial call to the time the patient arrives at the destination (ED or trauma center). Our aim in the study is to obtain estimates of actual time involved in EMS response, from the initial call to the arrival of the patient at an ED or trauma center. Our intent is to evaluate these times as a function of variables mentioned above, including distance, communication coverage, dispatch policies, etc. As a subpart of assessing EMS response times, we will look specifically at response times in tribal areas in California.

Learn more about this project on the CSCRS website.