ObjectiveTo explore the possible association between early injury assessment indexes and the length of stay (LOS) in first-line hospitals, in order to help the hospitals take advantage of resource effectively and transfer victims reasonably during earthquakes. MethodWe retrospectively analyzed the medical information of 3 576 traumatic patients injured in the Wenchuan Earthquake who were transferred to 242 first-line medical institutes between 14:28, May 12th and 14:30, May 19th in 2008. Three kinds of 15 variables were extracted for the analysis, including gender, age, heart or lung disease, pre-hospital time, head injury, trunk injury, open injury, crush injury, asphyxia, body temperature, heart rate, respiration, systolic blood pressure, diastolic blood pressure, and Glasgow coma score. Multiple stepwise linear regression analysis was performed to identify the factors associated with LOS. ResultsThe multiple linear regression analysis showed that age as well as other six factors affected LOS significantly (P<0.05). The partial regression coefficients of age, pre-hospital time, head injury, trunk injury, crush injury, complication of cardiac or pulmonary disease, and Glasgow coma score were -0.062, 0.157, 3.703, 4.111, 12.602, 14.762 and -1.312, respectively. ConclusionsEarthquake trauma patients with older age, long pre-hospital time, head injury, trunk injury, heart or lung disease, crush injury, and lower Glasgow coma score are at increased risk for extended LOS.