 Setting and Subjects This IRB-approved and HIPAA-compliant prospective randomized controlled trial was conducted from January 1, 2012 to December 31, 2013 in the ED of an urban Level-I adult trauma center. Imaging CDS was deployed for all CTPE requests throughout the study period as previously reported. Ordering providers could ignore the evidence presented in CDS and proceed with CTPE requests deviating from evidence-based guidelines without interference. The investigators included all attending emergency physicians and, prior to randomization, stratified them into quartiles by 2012 CTPE use. Physicians were randomized by quartile into two groups using a random number generator: the intervention group received individualized feedback reports on CTPE adherence to EBG, use defined as number of CTPEs per 1,000 patients, and yield percentage of CTPEs positive for PE, and the control group did not. 