Traumatic Brain Injury Among Drivers in Passenger Vehicles

Traumatic Brain Injury Among Drivers in Passenger Vehicles in Kentucky, 1997 State Injury Prevention Program Kentucky Injury Prevention and Research Center University of Kentucky School of Public Health CODES Technical Assistance Meeting Portland, ME June, 2000 Creation of TBI Data Set Level I Trauma Centers that Treat Kentuckians Creation of TBI Data Set File Linkages Trauma Registries UB92 Link and Remove Duplicates Filter TBI’s TBI Data Set Death Certificates Creation of TBI Data Set Results of Trauma-UB92-Death Certificates Linkage Number of TBI’s After Unduplication= 3,244 TBI Rate = 86/100,000 Preparation of Crash Data Set  Passengers were omitted because Kentucky police only collect date of birth for drivers. Occupants Unknown 1% Passnegers 24% Drivers 75% Preparation of Crash Data Set  Commercial vehicles and motorcycles were omitted Vehicle Type Commercial 3% Passenger 97% Crash-TBI Linkage • 580 TBI’s linked to drivers • Of these, 386 were ecoded as MV drivers • 194 were e-coded as MV non-traffic or passengers, or were not e-coded • Validation of the matches indicates possible e-coding issues 225,000 drivers 3,244 TBI’s Crash-TBI Linkage Estimate of False Negative Rate Data Source Hospital Discharge Death Certificates UK Trauma Reg. UL Trauma Reg. Kosair Trauma Reg. E-coded Number MV Driver Linked 126 142 68 275 12 76 114 54 137 5 Percent Linked 60% 80% 79% 50% 42% Total 623 386 62% Bivariate Analyses Measured association between TBI/No TBI outcome and:       Driver gender Driver age Seat belt use Posted speed limit Crash location Vehicle size (VIN)       Vehicle body type Type of crash Area of vehicle struck Type of roadway Weather Roadway condition • Number of drivers having TBI is 580 • Number of drivers having no TBI is approximately 225,000 Bivariate Analysis of Gender and TBI Lower Upper 95% C.I. Odds 95% C.I. Gender Limit Ratio Limit Male vs. Female 1.17 1.39 1.64 p-value 0.0057 • Male drivers were 1.39 times more likely to suffer a TBI as a result of a crash than were female drivers. Bivariate Analysis of Age and TBI Lower Upper 95% C.I. Odds 95% C.I. Age Limit Ratio Limit <=19 vs. >=20 1.10 1.36 1.70 p-value - • Drivers 19 years of age or younger were 1.36 times more likely to suffer a TBI as a result of a crash than were drivers 20 years of age or older. Bivariate Analysis of Seat Belt Use and TBI Lower Seat 95% C.I. Belt Used Limit No vs. Yes 10.8 Odds Ratio 12.7 Upper 95% C.I. Limit 15.1 p-value <0.001 • Unbelted drivers were 12.7 times more likely to suffer a TBI as a result of a crash than were belted drivers. • “Seat belt” in this test includes “lap belt,” “harness/lap belt,” “harness only,” and “other passenger restraint.” • “No seat belt” includes “installed, not in use” and “not installed” Other Bivariate Analyses Lower Upper 95% C.I. Odds 95% C.I. Variable Limit Ratio Limit Speed Limit >= 55 5.0 6.0 7.2 vs. Speed Limit < 55 Rural vs. Urban 3.8 4.5 5.4 DUI vs. No DUI 8.0 9.7 11.8 p-value <0.001 <0.001 <0.001 Variables Still to be Tested Vehicle size  Vehicle body type  Type of crash  Area of vehicle struck  Type of roadway  Weather  Roadway condition 