ABSTRACT The diagnostic process unfolds across multiple settings over time. Risk factors for error in each setting may vary, but for the patient, once a serious diagnostic error occurs, the specific clinical area where it happened is unimportant. Outpatient and inpatient settings have similar rates of diagnostic harm. Interactions within and between clinical teams and settings may either create resilience or increase risks for failure. Resilience engineering, or Safety II, is based on the concept that safety is a consequence of adaptations to the changing conditions of a system’s function. Robust communication supports a shared mental model that may create diagnostic resilience. Currently, clinician-patient/family communication along the diagnostic journey is haphazard. For example, pediatricians consistently fail to tell parents about “red flags” which are signs of a serious complication requiring immediate attention. Among children with chronic conditions at home, we found that 14% had serious diagnostic delays caused by parental misunderstanding of instructions. Pediatric diagnostic safety is understudied, and overall rates and types of outpatient pediatric diagnostic errors is unknown. To support robust communication with families of hospitalized children, we developed a structured communication intervention (PFC I-PASS) which reduces medical errors by 38%. I-PASS has been pilot tested for use during hospital discharge with similar success. Secondary analyses suggests that I-PASS may be effective at reducing diagnostic errors. PFC I-PASS has not been used in the outpatient setting and its impact on diagnostic safety has not been tested. Among children with multiple chronic conditions, we aim to: 1. Characterize the diagnostic journey, focusing on successes, errors, and patient/family and clinician communication; 2. Adapt PFC I-PASS to create Outpatient PFC I-PASS, a structured communication intervention for patients/families and clinicians in the outpatient setting; 3. Evaluate the effectiveness of PFC I- PASS (outpatient and discharge) to improve patients/family and clinician communication and experience, and to reduce errors and harm. The proposed Diagnostic Center of Excellence is comprised of two cores: a Methods Core and an Education and Dissemination Core. Cores include expertise in the diagnostic safety, Safety I and II, communication, medical education, and health disparities. The cores will work with Patient and Parent, Clinician, and Health System Leader Advisory Panels. At Boston Children’s Hospital, Cincinnati Children’s Hospital Medical Center and Children’s Hospital of Philadelphia, to address aims, we will employ observations, interviews, simulation, surveys, chart review, using S1 and S2 approaches. We will evaluate the impact of adapted PFC-IPASS on diagnostic errors using interrupted time series analysis. Methods will be immediately available to other Centers of Diagnostic Excellence and, through several networks, to over 200 health systems. Combining S1 and S2 approaches to characterize the diagnostic journey and test interventions has the potential to transform patient safety science.

PROJECT NARRATIVE The diagnostic process unfolds longitudinally across settings over time; diagnostic harm occurs with similar frequency in outpatient and in-patient settings along this journey. Communication failures underlying diagnostic errors suggests an opportunity for robust communication among teams and with children and families. Using S1 and S2 approaches, among children with multiple chronic conditions, we will characterize the diagnostic journey, focusing on patient/family-clinician communication, and adapt and test the impact of an outpatient structured family-centered communication intervention (PFC I-PASS) on diagnostic success, errors and harm.