Medication errors observed in 36 health care facilities

Arch Intern Med. 2002 Sep 9;162(16):1897-903. doi: 10.1001/archinte.162.16.1897.


Background: Medication errors are a national concern.

Objective: To identify the prevalence of medication errors (doses administered differently than ordered).

Design: A prospective cohort study.

Setting: Hospitals accredited by the Joint Commission on Accreditation of Healthcare Organizations, nonaccredited hospitals, and skilled nursing facilities in Georgia and Colorado.

Participants: A stratified random sample of 36 institutions. Twenty-six declined, with random replacement. Medication doses given (or omitted) during at least 1 medication pass during a 1- to 4-day period by nurses on high medication-volume nursing units. The target sample was 50 day-shift doses per nursing unit or until all doses for that medication pass were administered.

Methods: Medication errors were witnessed by observation, and verified by a research pharmacist (E.A.F.). Clinical significance was judged by an expert panel of physicians.

Main outcome measure: Medication errors reaching patients.

Results: In the 36 institutions, 19% of the doses (605/3216) were in error. The most frequent errors by category were wrong time (43%), omission (30%), wrong dose (17%), and unauthorized drug (4%). Seven percent of the errors were judged potential adverse drug events. There was no significant difference between error rates in the 3 settings (P =.82) or by size (P =.39). Error rates were higher in Colorado than in Georgia (P =.04)

Conclusions: Medication errors were common (nearly 1 of every 5 doses in the typical hospital and skilled nursing facility). The percentage of errors rated potentially harmful was 7%, or more than 40 per day in a typical 300-patient facility. The problem of defective medication administration systems, although varied, is widespread.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Accreditation
  • Cohort Studies
  • Colorado
  • Georgia
  • Health Services Research / methods
  • Hospitals / classification
  • Hospitals / standards*
  • Hospitals / statistics & numerical data
  • Humans
  • Joint Commission on Accreditation of Healthcare Organizations
  • Medication Errors / statistics & numerical data*
  • Medication Systems / standards*
  • Medication Systems / statistics & numerical data
  • Medication Systems, Hospital / standards
  • Medication Systems, Hospital / statistics & numerical data
  • Nursing Staff
  • Pharmacists
  • Pharmacy Service, Hospital / standards
  • Pharmacy Service, Hospital / statistics & numerical data
  • Prospective Studies
  • Quality Assurance, Health Care* / methods
  • Reproducibility of Results
  • Skilled Nursing Facilities / classification
  • Skilled Nursing Facilities / standards*
  • Skilled Nursing Facilities / statistics & numerical data
  • United States