title: Underreporting of conflicts of interest in clinical practice guidelines: cross sectional study.
abstract: BACKGROUND
  Conflicts of interest affect recommendations in clinical guidelines and disclosure of such conflicts is important. However, not all conflicts of interest are disclosed. Using a public available disclosure list we determined the prevalence and underreporting of conflicts of interest among authors of clinical guidelines on drug treatments.
  
  
  METHODS
  We included up to five guidelines published from July 2010 to March 2012 from each Danish clinical specialty society. Using the disclosure list of the Danish Health and Medicines Authority, we identified author conflicts of interest and compared them with the disclosures in the guidelines. For each guideline we extracted methodological characteristics of guideline development.
  
  
  RESULTS
  Forty-five guidelines from 14 specialty societies were included. Of 254 authors, 135 (53%) had conflicts of interest, corresponding to 43 of the 45 guidelines (96%) having one or more authors with a conflict of interest. Only one of the 45 guidelines (2%) disclosed author conflicts of interest. The most common type of conflict of interest (83 of the 135) was being a consultant, an advisory board member or a company employee. Only 10 guidelines (22%) described the methods used for guideline development, 27 (60%) used references in the text and 11 (24%) graded the types of evidence.
  
  
  CONCLUSIONS
  Conflicts of interest were common, but disclosures were very rare. Most guidelines did not describe how they were developed and many did not describe the evidence behind specific recommendations. Publicly available disclosure lists may assist guideline issuing bodies in ensuring that all conflicts are disclosed.
authors: The Nordic Cochrane Centre, Rigshospitalet Department 7811, Blegdamsvej 9, DK-2100, Copenhagen Ø, Denmark.
authors: Julie Bolette Brix
authors: JB
authors: Bindslev
authors: Jeppe
authors: J
authors: Schroll
authors: Peter C
authors: PC
authors: Gøtzsche
authors: Andreas
authors: A
authors: Lundh
mesh_terms: D016265:Conflict of Interest / Q000191:economics*; D003430:Cross-Sectional Studies; D003718:Denmark; D030881:Disclosure / Q000941:ethics / Q000706:statistics & numerical data*; D005378:Financial Support / Q000941:ethics*; D006801:Humans; D007182:Income; D008511:Medicine; D017410:Practice Guidelines as Topic / Q000592:standards*; D015995:Prevalence; D012017:Referral and Consultation / Q000191:economics / Q000941:ethics; D012108:Research Personnel / Q000191:economics / Q000941:ethics; D057566:Self Report / Q000191:economics* / Q000592:standards; D012955:Societies, Medical; D013663:Teaching / Q000191:economics / Q000941:ethics
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