Injury severity scoring: influence of timing and nurse raters on accuracy

The Abbreviated Injury Scale (AIS) and its incorporation into the Injury Severity Score (ISS) have become accepted as objective ways to quantitate the severity of trauma. To examine the practicality of using critical care nurses to initiate injury scoring within the first 24 hours of admission, a prospective study was undertaken. Nurses on the trauma intensive care unit were asked to calculate the ISS in patients admitted to the unit over a 4-month period. Scoring was completed within 24 hours of admission and recorded on an edited single-page chart constructed from the 1980 revision of the AIS. All patients were followed up until discharge, and the ISS was reviewed in the light of discharge diagnoses. One hundred four patients were studied, and accurate scores were calculated in 54 patients (51.9%). In three patients (2.9%) the single-page chart did not allow accurate scoring, and in 18 patients (17.3%) the diagnoses noted subsequent to the scoring time frame resulted in inaccuracy. Human errors resulted in inaccuracy in 28% of patients. In comparison with a concurrent study involving surgical residents, human error rates were similar. However, scoring within 24 hours, as opposed to 72 hours, resulted in significantly more errors related to diagnostic uncertainty. Initiation of the scoring process soon after admission, with subsequent correction during the hospital course, allows important information to be available at the earliest time.