title: Caution required when relying on a colleague's advice; a comparison between professional advice and evidence from the literature.
abstract: BACKGROUND
  Occupational Physicians rely especially on advice from colleagues when answering their information demands. On the other hand, Evidence-based Medicine (EBM) promotes the use of up-to-date research literature instead of experts. To find out if there was a difference between expert-based practice and EBM we compared professional advice on occupational health topics with best evidence from the literature.
  
  
  METHODS
  We asked 14 occupational physicians to consult their usual information sources on 12 pre-conceived occupational health problems. The problems were presented in the form of case vignettes which contained sufficient clinical information to be used by the occupational physicians for the consultation of their experts. We had searched the literature for the best available evidence on the 12 problems, which made it possible to answer the clinical questions with a clear yes or no.
  
  
  RESULTS
  The cases could be used by the occupational physicians as arising from their own practice. All together the occupational physicians consulted 75 different experts. Almost half of the consulted experts were near colleagues, 10% were industrial hygienists, 8% medical specialists and the rest had a varied background. Fifty three percent (95% confidence interval 42% to 65%) of all professional advice was not in line with the research literature. In 18 cases (24%) professional advice explicitly referred to up-to-date research literature as their used source. These cases were substantially less incorrect (17%) than advice that had not mentioned the literature as a source (65%) (difference 48%, 95% Confidence Interval from 27% to 69%).
  
  
  CONCLUSIONS
  Advice that occupational physicians routinely get in their daily practice differs substantially from best evidence from the literature. Occupational physicians who ask professional advice should always ask about the evidence of this advice.
authors.affiliation: Coronel Institute for Occupational and Environmental Health, Academic Medical Centre, 1100 DE Amsterdam, The Netherlands. f.g.schaafsma@amc.uva.nl
authors.forename: Frederieke
authors.initials: F
authors.lastname: Schaafsma
authors.forename: Jos
authors.initials: J
authors.lastname: Verbeek
authors.forename: Carel
authors.initials: C
authors.lastname: Hulshof
authors.forename: Frank
authors.initials: F
authors.lastname: van Dijk
mesh_terms: D000328:Adult; D001291:Attitude of Health Personnel; D019317:Evidence-Based Medicine; D005260:Female; D006801:Humans; D007255:Information Services / Q000592:standards / Q000706:statistics & numerical data*; D033183:Interdisciplinary Communication; D008297:Male; D008511:Medicine; D008875:Middle Aged; D009426:Netherlands; D009787:Occupational Medicine / Q000592:standards*; D012017:Referral and Consultation / Q000706:statistics & numerical data; D013038:Specialization; D011795:Surveys and Questionnaires