Objective: To investigate adverse event free admissions as a potential, patient-centered indicator aligned directly with the goal of patient safety—freedom from harm.
Background: Preventable adverse event rates in healthcare could be further reduced. These are generally measured separately, one adverse event at a time. However, this does not reveal whether different patients are affected or the same patients are experiencing multiple events.
Methods: We examined Medicare inpatient hospital administrative datasets for 2009 to 2011, processed using standard criteria. Events were (i) death within 30 days, (ii) unplanned readmissions within 30 days, (iii) long length of stay, (iv) healthcare acquired infections, and (v) established patient safety indicators not present on admission. We defined adverse event free admissions as those without record of any of these events. National rates were calculated by diagnosis group. Risk-adjusted hospital-specific rates of adverse event free admissions were calculated using colorectal procedures as an example.
Results: There were 23,991,193 admissions after exclusions. Approximately, 64% went through the acute inpatient Medicare system without record of anything untoward. Multiple events were recorded in 22·7% admissions; 15% of these experienced more than 2 adverse events. Risk-adjusted hospital-specific rates of adverse event free admissions for colorectal procedures showed 131 out of 3786 hospitals below the 99·8% lower control limit of the national upper quartile.
Conclusions: Overall, only 60% of admissions were recorded as adverse event free. Multiple adverse events were common. Even if events are under recorded, this measure could provide an easily understandable and useful baseline for clinicians and managers.
*Department of Primary Care and Public Health, Dr Foster Unit at Imperial College London, London, UK
†Department of Surgery and Cancer, Imperial College London, St Mary's Hospital, London, UK.
Reprints: Alice King, PhD, Department of Primary Care and Public Health, Dr Foster Unit at Imperial College London, 3 Dorset Rise, London EC4Y 8EN, UK. E-mail: firstname.lastname@example.org.
Disclosure: The Dr Foster Unit at Imperial College London is partially funded by a grant from Dr Foster, a private healthcare information company. The Dr Foster Unit at Imperial is affiliated with the National Institute of Health Research (NIHR) Imperial Patient Safety Translational Research Centre. The NIHR Imperial Patient Safety Translational Centre is a partnership between the Imperial College Healthcare NHS Trust and Imperial College London. The Dr Foster Unit at Imperial College is grateful for support from the NIHR Biomedical Research Centre funding scheme.
Author Contributions: A. K. contributed in the literature search, figures, study design, data analysis, data interpretation, drafting manuscript, and final approval of manuscript to be published. A. B. contributed in the data interpretation, revising manuscript critically for important intellectual content, and final approval of manuscript to be published. O. F. contributed in the data interpretation, revising manuscript critically for important intellectual content, and final approval of manuscript to be published. P. A. contributed in the study design, data , and revising manuscript critically for important intellectual content and final approval of manuscript to be published.
The grant sponsors were not involved in any aspect pertinent to the study or the decision to publish.
The Centers for Medicare and Medicaid Services data provider reviewed the data application and approved it, for these administrative data this is the only ethics approval required.
The authors declare no conflicts of interest.