Project Summary: Diagnostic error is believed to be the most common type of patient safety event. Affecting between 5-10% of all patient encounters, it results in significant patient morbidity and mortality. Ambulatory care is especially susceptible to this, with diagnostic errors outnumbering other types 6:1 and 5% of patients seeking ambulatory care experiencing diagnostic error. Comprised of delayed and missed diagnosis, diagnostic error is frequently the consequence of the inability to effectively access and/or synthesize complex medical information for medical decision making. With the adoption of the HITECH Act over 95% of hospitals and 80% of office based practice utilize Electronic Health Records (EHRs) as their primary source of patient information. With the rapid expansion of EHRs, there is growing appreciation of the myriad of ways in which EHRs contribute to failures in information gathering and/or synthesis. These EHR use errors are often a combination of system design issues and poor user training. Simulation affords a powerful tool to both study, in a systematic way, the means in which EHRs contribute to said errors as well as provide a powerful training tool. We previously demonstrated that hi-fidelity EHR based simulation exercises in the ICU, using purposively designed EHR charts, uncovers the contribution of EHR use errors to diagnostic error. Participation in these exercises improves the recognition of embedded trends in patient information required for effective diagnostic accuracy by 50%. While we have created a number of simulation based exercises for critical care, the workflow, cognitive errors and EHR chart structure are fundamentally different for ambulatory care, representing a greater degree of longitudinal care and the need to process information acquired across multiple individual encounters. This places even more importance on information loss during transitions of care. Further, a number of barriers exist to implementation of EHR based simulation activities at most medical centers, an issue magnified in community practices. Therefore the goal of this proposal is to create and validate a turn-key library of EHR based simulations to improve diagnostic safety in ambulatory care which is both generalizable and scalable. In Aim #1, we will perform our problem analysis by using a combination of administrative data from the Pennsylvania Patient Safety Authority and claims data from The Doctors Company to identify diagnoses at risk for diagnostic error in ambulatory care and EHR use errors associated with said errors. We will integrate these data to create a rubric to allow for the design of a comprehensive EHR based simulation library to study and reduce diagnostic error across the 5 major ambulatory specialties. In Aim #2, we will develop these simulations for 5 ambulatory specialties. We will in-turn validate the ability of the simulation activities to serve as a training tool to fundamentally change EHR use patterns a...