Patient-Reported Diagnostic Safety Events in Ambulatory Care Settings: A National Survey of Systemic Influences, Disparities and Persisting Consequences - Project Summary Diagnostic errors, delays, and related problems have been shown to be widespread in outpatient settings. Patient and family reports of these experiences offer a vital perspective on the scope, causes, and consequences of these mishaps. Yet, to date, information regarding patient experiences has been quite limited in the U.S., largely involving inpatient treatment or limited samples of patients from a few health systems or self-selected patient advocacy groups. This project would provide the first nationally representative estimates of Americans’ experiences with and concerns about diagnostic safety in ambulatory care. Deploying a survey incorporating several innovative survey methods, the study would (a) more reliably identify patient-reported safety events than in past surveys, (b) more fully elicit patient- and family-reported narrative accounts of those events, and (c) more consistently track the extended consequences of diagnostic problems. Data would be collected from 3,300 U.S. households that experienced diagnostic problems between 2020 and 2025. A sample this size makes possible comparisons across multiple settings (including newly emergent sites like urgent care clinics) and among different subgroups of patients, including those most marginalized historically. Because establishing an accurate, timely diagnosis is often challenging for clinicians and confounding to patients and their families, diagnostic problems are common in every healthcare system. But American healthcare financing and delivery systems are especially fragmented. We hypothesize that this fragmentation elevates the risks and harms of diagnostic breakdowns, particularly in outpatient settings. The study will test these hypothesis for three forms of insecurity induced by fragmentation (a) coverage insecurity, linked to anxieties about what healthcare insurance will cover, (b) guidance insecurity, emerging from patients’ difficulty identifying a clinician who can help them navigate the diagnostic process, and (c) process insecurity, emerging when multiple clinicians and care settings are associated with the diagnosis, leaving patients with inconsistent expectations for how the diagnostic process will unfold. Because all three forms of insecurity vary greatly within the American healthcare, we can both empirically assess the impact of fragmentation on diagnostic outcomes and estimate the potential benefits of reducing these three forms of fragmentation.