title: Reliability and validity of the cross-culturally adapted French version of the Core Outcome Measures Index (COMI) in patients with low back pain.
abstract: OBJECTIVE
  To conduct a cross-cultural adaptation of the Core Outcome Measures Index (COMI) into French according to established guidelines.
  
  
  METHODS
  Seventy outpatients with chronic low back pain were recruited from six spine centres in Switzerland and France. They completed the newly translated COMI, and the Roland Morris disability (RMQ), Dallas Pain (DPQ), adjectival pain rating scale, WHO Quality of Life, and EuroQoL-5D questionnaires. After ~14 days RMQ and COMI were completed again to assess reproducibility; a transition question (7-point Likert scale; "very much worse" through "no change" to "very much better") indicated any change in status since the first questionnaire.
  
  
  RESULTS
  COMI whole scores displayed no floor effects and just 1.5% ceiling effects. The scores for the individual COMI items correlated with their corresponding full-length reference questionnaire with varying strengths of correlation (0.33-0.84, P < 0.05). COMI whole scores showed a very good correlation with the "multidimensional" DPQ global score (Rho = 0.71). 55 patients (79%) returned a second questionnaire with no/minimal change in their back status. The reproducibility of individual COMI 5-point items was good, with test-retest differences within one grade ranging from 89% for 'social/work disability' to 98% for 'symptom-specific well-being'. The intraclass correlation coefficient for the COMI whole score was 0.85 (95% CI 0.76-0.91).
  
  
  CONCLUSIONS
  In conclusion, the French version of this short, multidimensional questionnaire showed good psychometric properties, comparable to those reported for German and Spanish versions. The French COMI represents a valuable tool for future multicentre clinical studies and surgical registries (e.g. SSE Spine Tango) in French-speaking countries.
authors: Division of Rheumatology, University Hospital of Geneva, Hôpital Beau-Séjour, 26 av. Beau-Séjour, 1211, Geneva 14, Switzerland. stephane.genevay@hcuge.ch
authors: Stéphane
authors: S
authors: Genevay
authors: Christine
authors: C
authors: Cedraschi
authors: Marc
authors: M
authors: Marty
authors: Sylvie
authors: S
authors: Rozenberg
authors: Pierre
authors: P
authors: De Goumoëns
authors: Antonio
authors: A
authors: Faundez
authors: Federico
authors: F
authors: Balagué
authors: François
authors: F
authors: Porchet
authors: Anne F
authors: AF
authors: Mannion
mesh_terms: D000328:Adult; D000368:Aged; D003431:Cross-Cultural Comparison; D004185:Disability Evaluation; D005260:Female; D005602:France; D006801:Humans; D017116:Low Back Pain / Q000175:diagnosis* / Q000523:psychology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement / Q000379:methods / Q000592:standards*; D011594:Psychometrics / Q000379:methods / Q000592:standards; D011795:Surveys and Questionnaires / Q000592:standards*; D016896:Treatment Outcome