title: The nosology-taxonomy of recent-onset arthritis: the experience of early-arthritis clinics.
abstract: OBJECTIVE
  To compare the conclusions of studies addressing the outcome of early-arthritis cohorts.
  
  
  METHODS
  The methodologies of previous reports on early-arthritis cohorts were examined, and their results and conclusions were compared.
  
  
  RESULTS
  Thirty-four reports on 23 cohorts of early arthritis were found. The methodology was poor in most studies, with numerous inclusion and exclusion biases, frequently short follow-up periods, and a lack of precision about the rationale for diagnosis. However, similar conclusions were reached on several points: a large number of cases of early arthritis remained undifferentiated and/or resolved spontaneously, about 80% of cases initially classified as undifferentiated or rheumatoid arthritis retained this diagnosis during follow-up, and the incidence of psoriatic arthritis in most studies was similar (2% to 4%). Conversely, there were striking discrepancies among studies concerning the frequency of crystal arthropathies (0% to 18%), spondyloarthropathy (1% to 33%) and rheumatoid arthritis (15% to 47%).
  
  
  CONCLUSIONS
  There appears to be a lack of agreement among researchers about the nosology and/or taxonomy of many cases of mild arthritis, despite the existence of classification criteria.
  
  
  CONCLUSIONS
  Recognition of cultural bias in the diagnosis of early arthritis could be a prerequisite for the optimization of new sets of criteria for the diagnosis of early rheumatoid arthritis and spondyloarthropathy.
authors: Department of Rheumatology, Hôtel-Dieu, CHU Nantes, 44093, Nantes-Cedex 01, France. jeanmarie.berthelot@chu-nantes.fr
authors: J M
authors: JM
authors: Berthelot
authors: A
authors: A
authors: Saraux
authors: Y
authors: Y
authors: Maugars
authors: A
authors: A
authors: Prost
authors: P
authors: P
authors: Le Goff
mesh_terms: D001168:Arthritis / Q000145:classification*; D005500:Follow-Up Studies; D006801:Humans; D016239:MEDLINE / Q000706:statistics & numerical data; D013997:Time Factors; D016896:Treatment Outcome