title: Systems analysis of adverse drug events. ADE Prevention Study Group.
abstract: OBJECTIVE
  To identify and evaluate the systems failures that underlie errors causing adverse drug events (ADEs) and potential ADEs.
  
  
  METHODS
  Systems analysis of events from a prospective cohort study.
  
  
  METHODS
  All admissions to 11 medical and surgical units in two tertiary care hospitals over a 6-month period.
  
  
  METHODS
  Errors, proximal causes, and systems failures.
  
  
  METHODS
  Errors were detected by interviews of those involved. Errors were classified according to proximal cause and underlying systems failure by multidisciplinary teams of physicians, nurses, pharmacists, and systems analysts.
  
  
  RESULTS
  During this period, 334 errors were detected as the causes of 264 preventable ADEs and potential ADEs. Sixteen major systems failures were identified as the underlying causes of the errors. The most common systems failure was in the dissemination of drug knowledge, particularly to physicians, accounting for 29% of the 334 errors. Inadequate availability of patient information, such as the results of laboratory tests, was associated with 18% of errors. Seven systems failures accounted for 78% of the errors; all could be improved by better information systems.
  
  
  CONCLUSIONS
  Hospital personnel willingly participated in the detection and investigation of drug use errors and were able to identify underlying systems failures. The most common defects were in systems to disseminate knowledge about drugs and to make drug and patient information readily accessible at the time it is needed. Systems changes to improve dissemination and display of drug and patient data should make errors in the use of drugs less likely.
authors.affiliation: Department of Health Policy and Management, Harvard School of Public Health, Boston, MA 02115, USA.
authors.forename: L L
authors.initials: LL
authors.lastname: Leape
authors.forename: D W
authors.initials: DW
authors.lastname: Bates
authors.forename: D J
authors.initials: DJ
authors.lastname: Cullen
authors.forename: J
authors.initials: J
authors.lastname: Cooper
authors.forename: H J
authors.initials: HJ
authors.lastname: Demonaco
authors.forename: T
authors.initials: T
authors.lastname: Gallivan
authors.forename: R
authors.initials: R
authors.lastname: Hallisey
authors.forename: J
authors.initials: J
authors.lastname: Ives
authors.forename: N
authors.initials: N
authors.lastname: Laird
authors.forename: G
authors.initials: G
authors.lastname: Laffel
mesh_terms: D001900:Boston / Q000453:epidemiology; D064420:Drug-Related Side Effects and Adverse Reactions; D006801:Humans; D007049:Iatrogenic Disease / Q000453:epidemiology; D008508:Medication Errors / Q000145:classification* / Q000706:statistics & numerical data; D008510:Medication Systems, Hospital / Q000458:organization & administration* / Q000706:statistics & numerical data; D011446:Prospective Studies; D012308:Risk Management; D013597:Systems Analysis