title: Investigating the dimension functioning from a condition-specific perspective and the qualifier scale of the International Classification of Functioning, Disability, and Health based on Rasch analyses.
abstract: OBJECTIVE
  This study aimed to explore to what extent the data collected for patients with low back pain, breast cancer, and stroke, based on the International Classification of Functioning, Disability and Health (ICF) Checklist, reflect the hypothesized single latent dimension functioning and whether the ICF qualifier scale expresses a clearly defined ordered sequence of response options.
  
  
  METHODS
  Data including ratings of 56 ICF categories for low back pain, 54 for breast cancer, and 84 for stroke were analyzed using the Rasch model.
  
  
  RESULTS
  For each health condition, most of the ICF categories fit the Rasch model. In most of them, one or two of the four threshold estimates were reversed before collapsing the response options. The collapsing strategy 01122 was proposed.
  
  
  CONCLUSIONS
  The fit residual statistics showed that most of the ICF categories selected for each of the health conditions reflect the single latent variable functioning. The ordering of the ICF qualifier scale was not consistent with the intended order.
authors.affiliation: Institute for Health and Rehabilitation Sciences, Research Unit for Biopsychosocial Health, Ludwig-Maximilians-University, Munich, Germany.
authors.forename: Cristina
authors.initials: C
authors.lastname: Bostan
authors.forename: Cornelia
authors.initials: C
authors.lastname: Oberhauser
authors.forename: Alarcos
authors.initials: A
authors.lastname: Cieza
mesh_terms: D000203:Activities of Daily Living; D001943:Breast Neoplasms / Q000145:classification* / Q000534:rehabilitation; D003430:Cross-Sectional Studies; D004185:Disability Evaluation; D006233:Persons with Disabilities / Q000145:classification* / Q000534:rehabilitation*; D005260:Female; D006801:Humans; D038801:International Classification of Diseases; D017116:Low Back Pain / Q000145:classification* / Q000534:rehabilitation; D008297:Male; D008962:Models, Theoretical; D012720:Severity of Illness Index; D018434:Sickness Impact Profile; D013223:Statistics as Topic; D020521:Stroke / Q000145:classification*; D000071939:Stroke Rehabilitation