title: Reliability, validity and responsiveness of the Portuguese version of the Knee injury and Osteoarthritis Outcome Score--Physical Function Short-form (KOOS-PS).
abstract: OBJECTIVE
  To test the reliability, validity and responsiveness of the Portuguese version of the Knee injury and Osteoarthritis Outcome Score--Physical Function Short-form (KOOS-PS).
  
  
  METHODS
  The Portuguese full KOOS and Medical Outcomes Study e 36 item Short-Form (SF-36) questionnaires, and a form of individual characteristics of the patients were applied to 85 subjects with knee osteoarthritis (OA).
  
  
  RESULTS
  Cronbach's alpha coefficient was 0.89 and intraclass correlation coefficient (ICC) was 0.85, certifying that KOOS-PS reliability was acceptable. Construct validity was supported by the confirmation of the five predefined hypotheses involving expected correlations between KOOS-PS scale, KOOS subscales and SF-36 subscales. An additional predefined hypothesis was also confirmed with the subjects that need walking aids obtaining higher KOOS-PS scale scores (P = 0.011). Responsiveness to 4 weeks of conventional physical therapy treatments and to a 6-week health education and exercise program was demonstrated with a standardized effect size of 0.88 and 0.50, and a standardized response mean of 1.21 and 0.73, respectively.
  
  
  CONCLUSIONS
  The Portuguese KOOS-PS evidenced acceptable psychometric characteristics.
authors.affiliation: Technical University of Lisbon, Faculty of Human Kinetics, Center for Research in Physiotherapy, Lisbon, Portugal. ruigoncalves@estescoimbra.pt
authors.forename: R S
authors.initials: RS
authors.lastname: Gonçalves
authors.forename: J
authors.initials: J
authors.lastname: Cabri
authors.forename: J P
authors.initials: JP
authors.lastname: Pinheiro
authors.forename: P L
authors.initials: PL
authors.lastname: Ferreira
authors.forename: J
authors.initials: J
authors.lastname: Gil
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D003431:Cross-Cultural Comparison; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000503:physiopathology* / Q000523:psychology; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000503:physiopathology* / Q000523:psychology; D010147:Pain Measurement; D011174:Portugal; D011788:Quality of Life / Q000523:psychology*; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D016896:Treatment Outcome