| Actively-Involved Persons |
These include all drivers or nonoccupants involved in a fatal crash.
Nonoccupants include pedestrians and pedalcyclists. The term “actively involved” qualifies persons whose actions and characteristics are significant determinants of the crash. |
| Alcohol Involvement |
Alcohol involvement is observed in a crash if any of the drivers or nonoccupants in the crash had a BAC of .01 or above.
Alcohol involvement with respect to a driver or nonoccupant is defined when the driver or nonoccupant had a BAC of .01 or above. |
| Alcohol-Related Crashes |
A crash is said to be alcohol related if any one of the actively-involved people in a police-reported fatal traffic crash had a BAC of .01 g/dL or greater (.01+). |
| Alcohol-Related Fatalities |
A fatality is said to be alcohol related if it occurred in a crash where any
one of the actively-involved people in the crash had a BAC of .01 g/dL or greater. |
| Any Alcohol |
A positive BAC value (BAC=.01+) for any driver or nonoccupant in the crash. |
| ARF |
Annual Report File of the Fatality Analysis Reporting System (FARS). A compilation of preliminary data on fatal motor vehicle traffic crashes each year in the United States. |
| BAC |
The blood alcohol concentration (BAC) that is determined either by police-administered tests on surviving persons or from the medical records of fatally-injured people. BAC is usually measured in grams per deciliter (g/dL) of blood, and plausible values in FARS range from .00 to .94+ g/dL. |
| Crash BAC |
The highest BAC among all the actively-involved people in the crash. For example, in a crash involving a vehicle and a pedestrian, if the driver of the vehicle had a BAC of .01 g/dL and the pedestrian had a BAC of .11 g/dL, the Crash BAC is .11 g/dL. |
Discriminate
Analysis |
A multivariate statistical technique for estimating linear functions of
variables, and using these linear functions to calculate the (posterior) probability to each of several mutually exclusive groups. |
| Driver BAC |
The BAC of any driver in a crash. |
| Had Alcohol Imputation |
BAC of .01 or above.
A procedure used to fill in missing data using statistical procedures. These procedures use the cases with known BAC values to learn about the variables that show significant relationship with the extent of BAC. This knowledge is in turn used on the characteristics of cases with missing BAC to “estimate” a value of BAC. |
Impairment
(Impaired) |
For the purposes of this document, a person is said to be impaired if his or her BAC is between .01 and .07 g/dL (.01-.07). |
| Injury Severity |
Presented as fatal or surviving. Any injury code other than fatal is treated as surviving. |
Intoxication
(Intoxicated) |
For the purposes of this document, a person is said to be intoxicated if his or her BAC is .08 g/dL or greater (.08+). |
| Multiple Imputation |
A peer-reviewed, well-accepted statistical procedure to estimate missing BAC. Each missing BAC is replaced with “multiple” BAC values which are then combined to estimate extent of alcohol involvement. Enables reporting of errors, confidence intervals, etc. |
| Nonoccupant |
Any person involved in a crash who is not the occupant of a motor vehicle. Pedestrians, pedalcyclists, people on rollerblades, skateboards, etc., are nonoccupants. |
| Person BAC |
The BAC of a driver or a nonoccupant. |
| Prior DWI Convictions |
Counts prior alcohol/drug convictions within three years from crash date. |
| Recidivism |
The tendency to repeatedly relapse into a criminal or delinquent habit such as Driving While Intoxicated (DWI). |
| Rural/Urban |
Land use based on Federal Highway Administration classification. |
| Weekday |
From 6 a.m. Monday to 5:59 p.m. Friday. |
| Weekend |
From 6 p.m. Friday to 5:59 a.m. Monday. |
| With Alcohol |
BAC of .01 or above. |