title: The impact of computerized physician order entry on medication error prevention.
abstract: BACKGROUND
  Medication errors are common, and while most such errors have little potential for harm they cause substantial extra work in hospitals. A small proportion do have the potential to cause injury, and some cause preventable adverse drug events.
  
  
  OBJECTIVE
  To evaluate the impact of computerized physician order entry (POE) with decision support in reducing the number of medication errors.
  
  
  METHODS
  Prospective time series analysis, with four periods.
  
  
  METHODS
  All patients admitted to three medical units were studied for seven to ten-week periods in four different years. The baseline period was before implementation of POE, and the remaining three were after. Sophistication of POE increased with each successive period.
  
  
  METHODS
  Physician order entry with decision support features such as drug allergy and drug-drug interaction warnings.
  
  
  METHODS
  Medication errors, excluding missed dose errors.
  
  
  RESULTS
  During the study, the non-missed-dose medication error rate fell 81 percent, from 142 per 1,000 patient-days in the baseline period to 26.6 per 1,000 patient-days in the final period (P < 0.0001). Non-intercepted serious medication errors (those with the potential to cause injury) fell 86 percent from baseline to period 3, the final period (P = 0.0003). Large differences were seen for all main types of medication errors: dose errors, frequency errors, route errors, substitution errors, and allergies. For example, in the baseline period there were ten allergy errors, but only two in the following three periods combined (P < 0.0001).
  
  
  CONCLUSIONS
  Computerized POE substantially decreased the rate of non-missed-dose medication errors. A major reduction in errors was achieved with the initial version of the system, and further reductions were found with addition of decision support features.
authors.affiliation: Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA. dwbates@bics.bwh.harvard.edu
authors.forename: D W
authors.initials: DW
authors.lastname: Bates
authors.forename: J M
authors.initials: JM
authors.lastname: Teich
authors.forename: J
authors.initials: J
authors.lastname: Lee
authors.forename: D
authors.initials: D
authors.lastname: Seger
authors.forename: G J
authors.initials: GJ
authors.lastname: Kuperman
authors.forename: N
authors.initials: N
authors.lastname: Ma'Luf
authors.forename: D
authors.initials: D
authors.lastname: Boyle
authors.forename: L
authors.initials: L
authors.lastname: Leape
mesh_terms: D016303:Clinical Pharmacy Information Systems; D020000:Decision Support Systems, Clinical; D004360:Drug Therapy, Computer-Assisted; D064420:Drug-Related Side Effects and Adverse Reactions; D006784:Hospitals, Teaching / Q000706:statistics & numerical data; D006801:Humans; D008404:Massachusetts; D016347:Medical Records Systems, Computerized; D008508:Medication Errors / Q000145:classification / Q000517:prevention & control* / Q000706:statistics & numerical data; D008510:Medication Systems, Hospital; D014584:User-Computer Interface