ObjectiveTo evaluate available characteristics and financial costs of malpractice cases among Advanced Practice Providers (Nurse Practitioners and Physician Assistants), trainees (medical students, residents, fellows) and attending physicians.MethodsA retrospective analysis of claims occurring in the emergency department from January 1, 2010 to December 31, 2019 contained in the Candello database. Cases were classified according to the provider type(s) involved: Nurse Practitioner (NP), Physician Assistant (PA), trainee, or cases which did not identify an extender as being substantially involved in the adverse event that resulted in the case (“no extender”).ResultsThere were 5,854 cases identified with a total gross indemnity paid of $1,007,879,346. Of these cases, 193 (3.3%) involved an NP, 513 (8.8%) involved a PA, 535 (9.1%) involved a trainee, and 4,568 (78.0%) were no extender. Cases where a trainee was involved account for the highest average gross indemnity paid whereas no extender cases are the lowest. NP and PA cases differed by contributing factors compared to no extender cases: Clinical Judgment (NP 89.1% vs no extender 76.8%, p<0.0001; PA 84.6% vs no extender, p < .0001), Documentation (NP 23.3% vs no extender 17.8%, p=0.0489; PA 25.9% vs no extender, p<0.0001) and Supervision (NP 22.3% vs no extender 1.8%, p<0.0001; PA 25.7% vs no extender p < 0.0001). Cases involving NPs and PAs had a lower percentage of high severity cases such as loss of limb or death (NP 45.6% vs no extender 50.2%, p=0.0004; PA 48.3% vs no extender, p < 0.0001).ConclusionsAdvanced Practice Providers (APPs) and trainees comprise approximately 21% of malpractice cases and 33% of total gross indemnity paid in this large national emergency department dataset. Understanding differences in characteristics of malpractice claims that occur in emergency care settings can be used to help to mitigate provider risk.