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 227% admissions; 15%
of these experienced more than 2 adverse events. Risk-adjusted hospitalspecific
rates of adverse event free admissions for colorectal procedures
showed 131 out of 3786 hospitals below the 998% 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.