MULTIPLE IMPUTATION OF MISSING BLOOD ALCOHOL CONCENTRATION (BAC) VALUES IN FARS
The National Highway Traffic Safety Administration (NHTSA) has undertaken several approaches to remedy the problem of missing blood alcohol test results in the Fatality Analysis Reporting System (FARS). The approach currently in use employs a linear discriminant model that estimates the probability that a driver or nonoccupant has a blood alcohol concentration (BAC) in grams per deciliter (g/dl) of 0.00, 0.01 to 0.09, or 0.10 and greater. The estimates are generated only for drivers and nonoccupants (pedestrians, pedalcyclists) for whom alcohol test results were not reported. The proposed methodology extends the current model by simulating specific values of BAC across the full range of possible values rather than estimating probabilities. By imputing ten values of BAC for each missing value, valid statistical inferences like variance, confidence intervals and deviation tests can be drawn. The estimation of discrete values also facilitates analysis by nonstandard boundaries of alcohol involvement (e.g., 0.08+).
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Corporate Authors:
Rainbow Technology Incorporated
17106 Thatcher Court
Olney, MD United States 20832National Highway Traffic Safety Administration
1200 New Jersey Avenue, SE
Washington, DC United States 20590 -
Authors:
- Rubin, D B
- SCHAFER, J L
- Subramanian, R
- Publication Date: 1998-10
Language
- English
Media Info
- Features: Appendices; References; Tables;
- Pagination: 34 p.
Subject/Index Terms
- TRT Terms: Blood alcohol levels; Estimating; Mathematical models; Probability; Values in measurement
- Identifier Terms: Fatality Analysis Reporting System
- Uncontrolled Terms: Missing data
- Subject Areas: Data and Information Technology; Highways; Safety and Human Factors; I81: Accident Statistics;
Filing Info
- Accession Number: 00759269
- Record Type: Publication
- Report/Paper Numbers: HS-808 816,, Technical Report
- Contract Numbers: DTNH22-94-D-07005
- Files: HSL, TRIS, USDOT
- Created Date: Jan 29 1999 12:00AM