title: Retractions in the medical literature: how many patients are put at risk by flawed research?
abstract: BACKGROUND
  Clinical papers so flawed that they are eventually retracted may put patients at risk. Patient risk could arise in a retracted primary study or in any secondary study that draws ideas or inspiration from a primary study.
  
  
  METHODS
  To determine how many patients were put at risk, we evaluated 788 retracted English-language papers published from 2000 to 2010, describing new research with humans or freshly derived human material. These primary papers-together with all secondary studies citing them-were evaluated using ISI Web of Knowledge. Excluded from study were 468 basic science papers not studying fresh human material; 88 reviews presenting older data; 22 case reports; 7 papers retracted for journal error and 23 papers unavailable on Web of Knowledge. Overall, 180 retracted primary papers (22.8%) met the inclusion criteria. Subjects enrolled and patients treated in 180 primary studies and 851 secondary studies were combined.
  
  
  RESULTS
  Retracted papers were cited over 5000 times, with 93% of citations being research related, suggesting that ideas promulgated in retracted papers can influence subsequent research. Over 28 000 subjects were enrolled-and 9189 patients were treated-in 180 retracted primary studies. Over 400 000 subjects were enrolled-and 70 501 patients were treated-in 851 secondary studies which cited a retracted paper. Papers retracted for fraud (n=70) treated more patients per study (p<0.01) than papers retracted for error (n=110).
  
  
  CONCLUSIONS
  Many patients are put at risk by retracted studies. These are conservative estimates, as only patients enrolled in published clinical studies were tallied.
authors.affiliation: MediCC, Medical Communications Consultants, LLC, 103 Van Doren Place, Chapel Hill, NC 27517, USA. g_steen_medicc@yahoo.com
authors.forename: R Grant
authors.initials: RG
authors.lastname: Steen
mesh_terms: D035843:Biomedical Research / Q000941:ethics / Q000592:standards*; D002986:Clinical Trials as Topic; D003142:Communication; D006801:Humans; D010353:Patient Education as Topic; D010361:Patients / Q000523:psychology*; D010506:Periodicals as Topic; D012180:Retraction of Publication as Topic; D015871:Scientific Misconduct / Q000941:ethics* / Q000523:psychology