Improving the E coding of hospitalizations for injury: do hospital records contain adequate documentation?

OBJECTIVES: Incomplete external cause of injury (E) coding limits the usefulness of hospital discharge data sets for injury surveillance and research. Hospital medical records were examined to determine whether they contained adequate cause of injury documentation to allow for more complete E coding of injury discharges.
METHODS: Medical records for a sample of discharges involving a principal diagnosis of injury from the Uniform Hospital Discharge Data Set for Rhode Island were selected. We assigned E codes to these discharges and compared our E codes with those of the discharge data set.
RESULTS: Documentation of cause of injury in the medical records was sufficient to allow assignment of a specific E code to 70% of the injuries for which no E codes or vague E codes were submitted on the Uniform Hospital Discharge Data Set. It was estimated that specific cause of injury documentation is available in the medical records of 80% of all injury discharges in Rhode Island; for approximately 90%, an E code describing at least the broad cause of injury could be assigned.
CONCLUSIONS: Rates of E coding can be substantially increased by making better use of existing documentation in medical records.