Washington State Patrol records for 1989 show that 2709 motorcyclists (2557 motorcycles, 40 motor scooters, and 112 mopeds) were involved in crashes on public roads, with 59 fatalities. Patient identifying codes could not be formulated for 619 (22.9%) of the Washington State Patrol crash records. Three hundred and eighty-six crash victims did not have a valid driver's license, and 233 with a valid license were not successfully linked to Department of Licensing data. These records, therefore, could not be linked to hospital discharge records and were excluded from the hospital data analyses (the records could, however, be included in several fatality analyses, as they did not strictly require linkage to hospital discharge data). Information to create patient identifying codes for fatally injured motorcyclists could be obtained from multiple-cause-of-death records.Patient identifying codes were generated for 2090 Washington State Patrol records. Ofthese, 399were linked successfully to hospital records. Ten additional records were added by linking previously
42 American Journal ofPublic Health January 1996, Vol. 86, No. 1
Motorcycle Helmet Use
unmatched fatality records to hospital records, bringing the total to 409 records. This was possible because death records could be used to generate patient identifyingcodes. These fatalities were among the Washington State Patrol recordsforwhich no Washington State Patrol patient identifying code could be generated due to lack of a valid driver's license or unsuccessful computer linkage to the Department of Licensing for information to complete the patient identifying code. Twenty-three of the 409 records did not have helmet use information and were excluded, yielding 386 hospitalizations for analysis. All 59 fatalities identified from Washington State Patrol records were linked to multiple-cause-of-death files. One non hospitalized, fatally injured motorcyclist was dropped because there was no helmet use information, yielding 58 fatalities for analysis.
Hospitalized Crash Victims
Most hospitalized motorcyclists were