Pediatric Appropriate Use Criteria for Outpatient Echocardiography: Practice Variations among Pediatric Cardiologists, Noncardiologist Subspecialists, and Primary Care Providers.

•The AUC performed well across all provider types, as measured by the low percentage of U indications (4%) and the observed relationship between greater appropriateness and higher yield of abnormal findings.•Pediatric cardiologists, noncardiologist subspecialists, and PCPs demonstrated distinct ordering patterns with varied appropriateness rates.•Noncardiologist subspecialists achieved the highest percentage of A studies and the lowest percentage of R studies.•The cardiologists' practices were broadly consistent with major national trends.•Incomplete documentation by the PCPs did not allow classification of almost a quarter of cases, highlighting the need for targeted quality improvement efforts.