Coding external causes of injury (E-codes) in Maryland hospital discharges 1979-88: a statewide study to explore the uncoded population.
 We examined the trends in hospital discharge E-coding in Maryland over a 10-year period.
 The overall proportion of E-coded discharges has increased from 40 percent in 1979 to 55 percent in 1988.
 E-coding was lower in the severely injured, the elderly, and patients with long hospital stays.
 Our findings demonstrate that E-code reporting varies because of the limited number of data fields available for coding of discharge diagnoses.
 Universal, systematic reporting of E-codes in hospital discharge data is essential if these data are to provide critically needed information about nonfatal injuries.
 Hospital discharge data formats should contain separate fields for E-codes and the use of these codes, we believe, should be mandated.
