['This study sought to prospectively study the impact of an appropriate use criteria (AUC)-based educational intervention on transthoracic echocardiography (TTE) ordering among house staff on the inpatient general internal medicine service at an academic medical center.', 'AUC for TTE were developed in response to concerns about inappropriate use of TTE. To date, educational interventions based on the AUC to reduce inappropriate use of TTE have not been prospectively studied.', 'A prospective, time series analysis of an educational intervention was conducted and then compared with TTE ordering on the same medical service during a control period. The intervention consisted of: 1) a lecture to house staff on the 2011 AUC for TTE; 2) a pocket card that applied the AUC to common clinical scenarios; and 3) biweekly e-mail feedback regarding ordering behavior. TTE ordering was tracked over the intervention period on a daily basis and feedback reports were e-mailed at 2-week intervals. The primary outcome was the proportion of inappropriate and appropriate TTE ordered during the intervention period.', 'Of all TTEs ordered in the control and study periods, 99% and 98%, respectively, were classifiable using the 2011 AUC. During the study period, there was a 26% reduction in the number of TTE ordered per day compared with the number ordered during the control period (2.9 vs. 3.9 TTE, p < 0.001). During the study period, the proportion of inappropriate TTE was significantly lower (5% vs. 13%, p < 0.001) and the proportion of appropriate TTE was significantly higher (93% vs. 84%, p < 0.001).'] Does an educational intervention reduce the rate of inappropriate echocardiograms on an inpatient medical service?