Multiple Patient Safety Events Within a Single Hospitalization

A National Profile in US Hospitals

Published In: American Journal of Medical Quality, v. 27, no. 6, Nov./Dec. 2012, p. 472-479

Posted on on January 01, 2012

by Hao Yu, Michael D. Greenberg, Amelia Haviland, Donna O. Farley

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Research Questions

  1. How often do multiple 'patient safety events' (MPSE) occur during a single hospitalization?
  2. Are certain groups more likely to experience them?
  3. What are the average length of stay and average hospital charges associated with multiple patient safety events?

The objective was to examine co-occurrence of iatrogenic events in US hospitals. Using Agency for Healthcare Research and Quality patient safety indicators (PSIs), the authors defined multiple patient safety events (MPSEs) as the occurrence of multiple PSIs during a single hospitalization. The National Inpatient Sample was analyzed to estimate the national prevalence of MPSEs, risk factors for MPSEs, and the average length of stay and average hospital charges associated with MPSEs. MPSEs occurred in approximately 1 in every 1000 hospitalizations, affecting more than 30 000 patients in 2004. Significant risk factors for MPSEs include age, black race, Medicare coverage, and treatment at urban teaching hospitals. Compared with all admissions, the average length of stay for MPSE admissions was 4 times longer, and the average charge for MPSE admissions was 8 times greater. Despite the low prevalence, MPSEs affect large numbers of hospital patients in America. MPSEs have distinct characteristics and are far more resource intensive than hospital admissions generally.

Key Findings

MPSEs occur in approximately one in every 1,000 hospitalizations.

Patients experiencing MPSE are more likely to be:

  • older
  • male
  • black
  • Medicare beneficiaries
  • residents of a low median-income zip code
  • hospitalized in an urban teaching hospital.

MPSE hospitalizations are lengthy and costly.

  • The average length of stay for MPSE hospitalizations was four times longer than the average for all hospitalizations.
  • Average costs were eight times greater.

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