TY - JOUR T1 - Diagnostic error in hospitals: finding forests not just the big trees JF - BMJ Quality & Safety JO - BMJ Qual Saf SP - 961 LP - 964 DO - 10.1136/bmjqs-2020-011099 VL - 29 IS - 12 AU - Laura Zwaan AU - Hardeep Singh Y1 - 2020/12/01 UR - http://qualitysafety.bmj.com/content/29/12/961.abstract N2 - Diagnostic errors in hospital medicine have mostly remained in uncharted waters.1 This is partly because several factors make measurement of diagnostic errors challenging. Patients are often admitted to hospitals with a tentative diagnosis and need additional diagnostic investigations to determine next steps. This evolving nature of a diagnosis makes it hard to determine when the correct diagnosis could have been established and if a more specific diagnosis was needed to start the right treatment.2 Hospitalised patients also may have diagnoses that are atypical or rare and pose dilemmas for treating clinicians. As a result, delays in diagnosis may not necessarily be related to a diagnostic error. Furthermore, what types of diagnostic errors occur in the hospital and their prevalence depends on how one defines them. Different approaches to define them have included counting missed, wrong or delayed diagnoses regardless of whether there was a process error;3 counting them only when there was a clear ‘missed opportunity’ – ie, something different could have been done to make the correct or timely diagnosis;4 or diagnostic adverse events (ie, diagnostic errors resulting in harm);5 all leading to views of the problem through different lenses.Two articles in this issue of the journal provide new insights into the epidemiology of diagnostic errors in hospitalised patients.6 7 Gunderson and colleagues conducted a systematic review to determine the prevalence of harmful diagnostic errors in hospitalised patients.6 Raffel and colleagues studied readmitted patients using established methods for diagnostic error detection and analysis to gain insights into contributing factors.7 Both studies advance the science of measurement and understanding of how to reduce diagnostic error in hospitals. We discuss the significance of the results for hospital medicine and implications for emerging research and practice improvement efforts.Gunderson and colleagues performed a … ER -