title: Keitel Functional Test for patients with rheumatoid arthritis: translation, reliability, validity, and responsiveness.
abstract: OBJECTIVE
  The purpose of this study was to translate the German Keitel Functional Test (KFT) into Danish and test it for reliability, concurrent and predictive validity, and responsiveness in patients with rheumatoid arthritis (RA).
  
  
  METHODS
  Translation of the KFT was performed according to international recommendations, and the translated version was tested twice by 2 observers for intraobserver and interobserver reliability, with a 1-week interval between assessments, in 20 patients with RA with stable disease activity. Validity was investigated by studying 2 patient groups: (1) 15 patients with long-lasting (median=6 years) active RA, tested before and after 2, 6, and 14 weeks of anti-tumor necrosis factor alpha (TNF-alpha) inhibitor therapy, and (2) 35 patients with early (median=0.25 year) RA, tested at years 0, 0.5, 1, and 2. Twenty-three patients in the early RA group also were tested at year 7. KFT, conventional clinical and biochemical markers of disease activity, and Health Assessment Questionnaire (HAQ) were used.
  
  
  RESULTS
  The translated KFT showed good intraobserver reliability (intraclass correlation coefficients [ICC]=.90 and .95, coefficient of variation [CV]=3.5%) and interobserver reliability (ICC=.99 and .92, CV=3.5%), and the KFT correlated with several measures of disease activity and, most closely, with the HAQ. The KFT was, in contrast to clinical disease activity measures, not sensitive to changes over time. Only baseline KFT data were significantly related to functional changes over a long period of time as measured by the KFT, and only in the early RA group.
  
  
  CONCLUSIONS
  The Danish translation of the KFT showed good reliability, acceptable concurrent validity, very poor responsiveness, and inconclusive results concerning predictive validity. The results of this study do not support the use of the KFT for monitoring function in clinical practice, as an outcome measure in clinical trials, or as a predictor of functional changes.
authors.affiliation: Department of Physiotherapy, Copenhagen University Hospital at Hvidovre, Copenhagen, Denmark. bente.holm@hvh.regionh.dk
authors.forename: Bente
authors.initials: B
authors.lastname: Holm
authors.forename: Soren
authors.initials: S
authors.lastname: Jacobsen
authors.forename: Henrik
authors.initials: H
authors.lastname: Skjodt
authors.forename: Mette
authors.initials: M
authors.lastname: Klarlund
authors.forename: Trine
authors.initials: T
authors.lastname: Jensen
authors.forename: Merete Lund
authors.initials: ML
authors.lastname: Hetland
authors.forename: Mikkel
authors.initials: M
authors.lastname: Ostergaard
mesh_terms: D000328:Adult; D001172:Arthritis, Rheumatoid / Q000145:classification* / Q000175:diagnosis / Q000503:physiopathology; D005260:Female; D006801:Humans; D007802:Language; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011594:Psychometrics; D012044:Regression Analysis; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires