Summary of "The Safety of Inpatient Health Care"

Summary published May 3, 2023

Summary by Aalok Agarwala, MD

The New England Journal of Medicine | January 2023

Bates DW, Levine DM, Salmasian H, Syrowatka A, Shahian DM, Lipsitz S, Zebrowski JP, Myers LC, Logan MS, Roy CG, Iannaccone C, Frits ML, Volk LA, Dulgarian S, Amato MG, Edrees HH, Sato L, Folcarelli P, Einbinder JS, Reynolds ME, Mort E. The Safety of Inpatient Health Care. N Engl J Med. 2023 Jan 12;388(2):142-153. doi: 10.1056/NEJMsa2206117. PMID: 36630622.


  • In this retrospective cohort study, the authors assessed the frequency, preventability, and severity of patient harm in a random sample of 2809 admissions from 3 large and 8 smaller Massachusetts hospitals during 2018.
  • Using a trigger method with identification of events recorded in the medical record known to be associated with adverse events followed by clinician confirmation, an adverse event was identified in 23.6% of admissions. Types of events included transfusion reaction, health care-associated infection, adverse drug event, pregnancy-related event, surgical or procedure-related event, or patient care event related to nursing care such as falls or pressure ulcers.
  • Of 978 adverse events identified, 222 (22.7%) were classified as preventable and 316 (32.3%) were classified as serious, resulting in harm that required substantial intervention or prolonged recovery. 6.8% of all admissions had a preventable adverse event, and 1.0% of all admissions had at least one preventable adverse event that was categorized as serious, life threatening, or fatal.
  • Adverse drug events were the most common type of event identified (39%), followed by surgical or procedural events (30.4%), patient care events (15%), and health care-associated infections (11.9%).
  • The authors conclude that adverse events remain common and preventable nearly one-fourth of the time. While voluntary reporting continues to be the primary mechanism by which adverse events are identified, the authors suggest that widespread use of electronic health records and advances in artificial intelligence will lead to better identification of adverse events.
  • The study identified considerable variation in adverse event rates among hospitals, with larger hospitals having rates 40% higher than smaller ones. The authors suggest that more reliable and routinely collected data could improve monitoring and implementation of improvement strategies, ultimately leading to decreased adverse event rates