TY - JOUR T1 - National adverse event analysis over time: current state and future directions JF - BMJ Quality & Safety JO - BMJ Qual Saf SP - 529 LP - 532 DO - 10.1136/bmjqs-2020-011965 VL - 30 IS - 7 AU - Emily L Aaronson AU - David W Bates Y1 - 2021/07/01 UR - http://qualitysafety.bmj.com/content/30/7/529.abstract N2 - The Harvard Medical Practice Study brought the issue of patient safety into the public eye and demonstrated that patients are often harmed by the care they receive.1 It used retrospective chart review to identify adverse events. Since its publication in 1991, considerable focus has been placed on trying to improve the methods for understanding the prevalence of harm in hospitals. These efforts have led to deeper understanding of the relative strengths and weaknesses of the tools we currently have for adverse event identification. Still, most organisations do not have robust approaches for tracking all types of harm routinely. Other efforts have sought to assess safety not just in hospitals but across national health systems, and at one point in time, and to track and trend.Developing better approaches for measuring safety routinely is critical if we are to understand how many patients are being harmed, what the primary causes are and whether care is getting safer or less safe. However, it is also work that needs to be contextualised and the limitations of our tools must be appreciated.2 3 The Irish National Adverse Event Study 2 (INAES-2) is presented in this issue.4 In this study, Connolly and colleagues used retrospective chart review to find adverse events at eight Irish hospitals in 2015 and compare these to previously reported data from 2009. Retrospective chart review was the first method used in this space5 6 and is still a mainstay for national studies assessing rates of adverse events,7–12 although approaches using claims data are also used widely and are much less expensive though much less sensitive.13 The original approach using retrospective chart review relied on information exclusively gathered from retrospective review of randomly selected medical records, but it has since been bolstered by the creation of … ER -