title: Preventable drug-related hospital admissions.
abstract: OBJECTIVE
  To estimate the prevalence of preventable drug-related hospital admissions (PDRAs) and to explore if selected study characteristics affect prevalence estimates.
  
  
  METHODS
  Keyword search of MEDLINE (1966-December 1999), International Pharmaceutical Abstracts (1970-December 1999), and hand search. Two reviewers independently selected studies published in peer-reviewed journals and extracted crude prevalence estimates and study characteristics. Trials had to specifically address consequences of drug therapy requiring hospital admission and include a quantitative preventability assessment. Stratified analysis and meta-regression were used to explore the association between study characteristics and prevalence estimates.
  
  
  RESULTS
  Fifteen studies reported a median PDRA prevalence of 4.3% (interquartile range [IQR] 3.1-9.5%). The median preventability rate of drug-related admissions was 59% (IQR 50-73%). No evidence of publication bias related to study size could be determined. Because the individual study results were highly heterogeneous (Cochran's Q = 176, df = 14; p < 0.001), no meta-analytic summary estimate was computed. Stratified analysis suggested an association between prevalence estimates and 3 study characteristics: exclusion of first admissions (readmission studies: average PDRA prevalence of 14.0 %, estimated prevalence OR = 3.7); mean age of admissions >70 (OR = 2.1); and inclusion of "indirect" drug-related morbidity, such as omission errors or therapeutic failure (OR = 1.9). There was little evidence of other associations with prevalence estimates, such as selection of specific hospital units, exclusion/inclusion of planned admissions, country, and specified methods of PDRA case ascertainment.
  
  
  CONCLUSIONS
  Drug-related morbidity is a significant healthcare problem, and a great proportion is preventable. Study methods in prevalence reports vary and should be considered when interpreting findings or planning future research.
authors.affiliation: Department of Pharmacy Health Care Administration, College of Pharmacy, University of Florida, Gainesville, FL 32610-0496, USA. almut@cop.ufl.edu
authors.forename: Almut G
authors.initials: AG
authors.lastname: Winterstein
authors.forename: Brian C
authors.initials: BC
authors.lastname: Sauer
authors.forename: Charles D
authors.initials: CD
authors.lastname: Hepler
authors.forename: Charles
authors.initials: C
authors.lastname: Poole
mesh_terms: D064420:Drug-Related Side Effects and Adverse Reactions; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D008508:Medication Errors / Q000517:prevention & control / Q000706:statistics & numerical data; D009017:Morbidity; D015995:Prevalence