title: The potential of ESSG spondyloarthropathy classification criteria as a diagnostic aid in rheumatological practice.
abstract: OBJECTIVE
  The European Spondylarthropathy Study Group (ESSG) criteria for the classification of spondyloarthropathies (SpA) were developed with the aim of unifying and facilitating international medical communication. We assessed the potential of ESSG criteria as a diagnostic aid for rheumatology practices in terms of sex and prevalence rate.
  
  
  METHODS
  Data from 2 similarly designed and developed studies conducted in France and Spain were examined. Data were obtained from 3,494 patients seen at rheumatology outpatient services (28 in each country). The sensitivity and specificity of each ESSG criterion (except the radiological one) were assessed in terms of sex and country. Patients were divided into 4 groups according to number of criteria present at the time of the study: Group I had neither inflammatory spinal pain (ISP) nor synovitis; Group 2 had ISP and/or synovitis; Group 3 ISP and/or synovitis plus one additional criterion; Group 4 ISP and/or synovitis plus more than one additional criterion. The predictive value was determined by using different prevalence rates.
  
  
  RESULTS
  A prevalence of 27.6% for male and 8.0% for female patients was found at Spanish services; prevalence in French services was 9.1% males and 3.2% females. No significant differences in sensitivity and specificity for each sex between French and Spanish individuals were detected; the overall sensitivity and specificity were similar for men and women. By contrast, there were differences between patients from the 2 countries regarding individual ESSG criteria; thus, inflammatory spinal pain and synovitis were less specific in the female and male Spanish patients, respectively, relative to the French patients.
  
  
  CONCLUSIONS
  ESSG criteria can be used meaningfully to aid diagnosis when the prevalence of SpA exceeds 10% and the patient meets more than one of the additional criteria, or when prevalence exceeds 30% and the patient meets only one additional criterion.
authors.affiliation: Servicio de Reumatologiá, Hospital Universitario Reina Sofía, Córdoba, Spain.
authors.forename: Elisa Muñoz
authors.initials: EM
authors.lastname: Gomariz
authors.forename: MazoAgustínCisnal
authors.initials: M
authors.lastname: del
authors.forename: Verónica Pérez
authors.initials: VP
authors.lastname: Guijo
authors.forename: Alejandro Escudero
authors.initials: AE
authors.lastname: Contreras
authors.forename: MaríadelCarmenMuñoz
authors.initials: M
authors.lastname: Villanueva
authors.forename: Eduardo Collantes
authors.initials: EC
authors.lastname: Estévez
mesh_terms: D005260:Female; D005602:France / Q000453:epidemiology; D006801:Humans; D008297:Male; D017410:Practice Guidelines as Topic; D015995:Prevalence; D012219:Rheumatology / Q000379:methods*; D012680:Sensitivity and Specificity; D013030:Spain / Q000453:epidemiology; D025242:Spondylarthropathies / Q000145:classification / Q000175:diagnosis* / Q000453:epidemiology