title: Influence of magnetic resonance of the knee on GPs' decisions: a randomised trial.
abstract: BACKGROUND
  Magnetic resonance imaging (MRI) of the knee for meniscus and ligament injuries is an accurate diagnostic test. Early and accurate diagnosis of patients with knee problems may prevent the onset of chronic problems such as osteoarthritis, a common cause of disability in older people consulting their GP.
  
  
  OBJECTIVE
  To assess the effect of early access to MRI, compared with referral to an orthopaedic specialist, on GPs' diagnoses and treatment plans for patients with knee problems.
  
  
  METHODS
  A multi-centre, pragmatic, randomised controlled trial.
  
  
  METHODS
  Five hundred and fifty-three patients with knee problems were recruited from 163 general practices across the UK from November 2002 to October 2004.
  
  
  METHODS
  Eligible patients were randomised to MRI or consultation with an orthopaedic specialist. GPs made a concomitant provisional referral to orthopaedics for patients who were allocated to imaging. GPs recorded patients' diagnoses, treatment plans, and their confidence in these decisions at trial entry and follow-up. Data were analysed as intention to treat.
  
  
  RESULTS
  There was no significant difference between MRI and orthopaedic groups for changes in diagnosis (P = 0.79) or treatment plans (P = 0.059). Significant changes in diagnostic and therapeutic confidence were observed for both groups with a greater increase in diagnostic confidence (P<0.001) and therapeutic confidence (P = 0.002) in the MRI group. There was a significant increase in within-group changes in diagnostic and therapeutic confidence.
  
  
  CONCLUSIONS
  Access to MRI did not significantly alter GPs' diagnoses or treatment plans compared with direct referral to an orthopaedic specialist, but access to MRI significantly increased their confidence in these decisions.
authors: Department of Health Sciences, York Trials Unit, Seebohm Rowntree Building, University of York, Heslington, York, YO10 5DD. sb143@york.ac.uk
authors: Stephen D
authors: SD
authors: Brealey
mesh_terms: D000293:Adolescent; D000328:Adult; D003657:Decision Making; D005194:Family Practice; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000175:diagnosis*; D007719:Knee Joint / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008592:Menisci, Tibial / Q000473:pathology; D008875:Middle Aged; D011364:Professional Practice; D012017:Referral and Consultation
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