Purpose To evaluate the effect of an institutional clinical triaging algorithm on the rate of multidetector computed tomography (CT) utilization in blunt abdominopelvic trauma (BAPT) over an 8-year period at an urban level 1 trauma center. Materials and Methods Adult patients (n = 13 096; mean age, 42 years; age range, 15-95 years) admitted with BAPT from January 1, 2006, to December 31, 2013, were included. Patients with BAPT were divided into two groups: those admitted before (referred to as the prealgorithm group, from January 1, 2006, to June 30, 2010) and after (referred to as the postalgorithm group, from July 1, 2010, to December 31, 2013) the implementation of an institutional clinical triaging algorithm. The following parameters were recorded from abdominopelvic CT study reports for the pre- and postalgorithm groups: number of abdominopelvic CT examinations at admission, number of abdominopelvic CT examinations with positive BAPT-related findings, injury severity score, length of hospital stay, and number of mortalities. The unpaired t test and χ2 analysis were used to determine significant differences. Results The percentage of patients admitted for BAPT who underwent an abdominopelvic CT study was 76.7% (5900 of 7688) in the prealgorithm group and 44.6% (2413 of 5408) in the postalgorithm group, a 32.1% decrease in use of CT (P < .001). The mean injury severity score increased from 10.1 ± 9.1 (standard deviation) to 13.3 ± 11.9 after implementation of the algorithm in patients admitted for BAPT who underwent abdominopelvic CT examination (P < .001). The percentage of abdominopelvic CT examinations with BAPT-related findings increased from 17.1% (1007 of 5900) to 19.8% (479 of 2413) (P = .003). There was a significant difference in average length of stay, from 4.8 days ± 7.0 to 4.2 days ± 6.2 (P < .001). Mortality decreased from 3.1% (242 of 7688) to 2.7% (148 of 5408) after implementation of the algorithm (P = .19). Conclusion The implementation of a clinical triaging algorithm resulted in decreased use of multidetector CT in patients who presented with BAPT to the emergency department. © RSNA, 2016.