title: Psychological distress confirmed as predictor of long-term back-related functional limitations in primary care settings.
abstract: OBJECTIVE
  Among the possible predictors of back pain outcomes that have been studied, indices of psychological distress have been found to have a high prognostic value. This study aimed at assessing the validity of a predictive model of long-term back-related functional limitations that is based on psychological distress, in a new sample of subjects.
  
  
  METHODS
  The study was conducted with 860 French-speaking workers who consulted for nonspecific back pain in primary care settings of the Quebec City area. They were interviewed at baseline and again 2 years later. Psychological distress and back-related functional limitations were measured respectively with items drawn from the Symptom Checklist 90 Revised and the Roland-Morris Disability Questionnaire. Analyses were conducted by forcing the model previously developed on a sample of English-speaking health maintenance organization (HMO) members of Washington state.
  
  
  RESULTS
  The model correctly classified 82% of subjects as to their functional limitation status at 2 years. The accuracy of the prediction was similar to that reported in the original study.
  
  
  CONCLUSIONS
  The fact that this predictive model of back-related functional limitations led to similar results in a different sample of subjects and in another language brings strong support to its validity.
authors.affiliation: Research Centre of the Laval University Affiliated Hospital, Hôpital du Saint-Sacrement, 1050, chemin Ste-Foy, Quebec City, Quebec G1S 4L8, Canada. clermont.dionne@uresp.ulaval.ca
authors.forename: Clermont E
authors.initials: CE
authors.lastname: Dionne
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001416:Back Pain / Q000175:diagnosis / Q000503:physiopathology / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D009784:Occupational Diseases / Q000523:psychology*; D011237:Predictive Value of Tests; D011320:Primary Health Care; D011379:Prognosis; D011446:Prospective Studies; D013315:Stress, Psychological / Q000523:psychology*