What is MMUCC?

The Model Minimum Uniform Crash Criteria Guideline (MMUCC) is a minimum, standardized data set for describing motor vehicle crashes and the vehicles, persons and environment involved. The Guideline is designed to generate the information necessary to improve highway safety within each state and nationally. This data set, originally published in the MMUCC Guideline, 1st Edition (1998), has been revised three times, most recently in the 4th Edition (2012), in response to emerging highway safety issues.

The 110 data elements presented in this document include 77 data elements to be collected at the scene, 10 data elements to be derived from the collected data, and 23 data elements to be obtained after linkage to driver history, injury and roadway inventory data. Definitions for the data elements match existing standards, unless modification was necessary to match current trends.

What Are the Benefits of MMUCC?

Implementation of MMUCC will improve the quality of state data and, subsequently, the national estimates based on these data. Standardized data elements and definitions enable the crash data to be shared and compared at all levels. Software for crash data entry is easier to develop for statewide implementation when the data elements and definitions are uniform. MMUCC recommends linkage to roadway inventory data, other traffic records, medical outcome, global positioning system location data, etc. to expand what is known about the crash and the persons involved. States, unable to link, are encouraged to collect the data elements, when feasible, at the scene until they develop linkage capabilities.

Comprehensive crash data are necessary to determine which countermeasures are most effective. This information is useful for targeting resources so they will have the most impact on reducing deaths, injuries, injury severity and health care costs.

What is the Intent of the MMUCC Data Elements?

MMUCC data describe the characteristics of the crash, the vehicle(s), person(s) and roadway involved. Crash data elements describe the date, time, location, first and most harmful events, type of crash, weather and contributing circumstances. Vehicle data elements describe the vehicle make, model, model year, type, function, actions, impact, sequence of events and damaged areas. Person data elements describe all involved persons by age, sex, injury status and type. Vehicle number, seating position, use of safety equipment are collected for all vehicle occupants. Driver status information, non-motorist status information, alcohol and drug involvement are collected for all drivers and non- motorists. EMS transport status is collected for all injured persons.

Derived MMUCC data elements reduce the data collection burden at the scene by converting collected data into new information. MMUCC data elements obtained after linkage to injury records identify the cost of traffic crashes and, ultimately, who pays. Data elements obtained after linkage to roadway inventory data describe the characteristics of the roadway where the crash occurred.

How Is MMUCC Updated?

The MMUCC update process, sponsored by the National Highway Traffic Administration and the Governors Highway Safety Association, provides for the greatest possible input so that MMUCC is perceived not as a product of any one organization but as something for which all stakeholders can claim ownership. More in-depth feedback is obtained in a series of meetings of the MMUCC expert panel, through input received at the annual International Forum for Traffic Records, and via the MMUCC website.

What Criteria Were Used to Develop MMUCC?

MMUCC consists of data elements that are needed by the highway safety community. Each data element includes a definition, set of attribute values and rationale. The attributes selected for each data element were considered a minimum set that states could expand to meet their state-specific needs. MMUCC is limited to the actual data elements, attributes and their definitions. The choice of implementation method is left to the states so that states do not have to revise the file structure of their existing data systems.

All states are encouraged to implement the MMUCC recommendations to: 1) report all crashes statewide involving death, personal injury, or property damage of $1,000 or more and all persons (injured and uninjured) involved in the crash and 2) incorporate the MMUCC data elements as presented in this Guideline.