title: Use of Rasch analysis to investigate structural validity of a set of movement control tests for the neck.
abstract: Movement control abilities are often reduced in persons with neck pain. In physiotherapeutic practice observational tests are frequently used to assess the impaired abilities. Several tests for movement control abilities are available, but no evidence exists on how to combine and interpret them.
  
  
  
  The aim was to investigate structural validity of a set of movement control tests with Rasch analysis.
  
  
  
  Cross-sectional study.
  
  
  
  Thirty persons with and thirty without neck pain were recruited for this study. All persons performed ten movement control tests. A partial credit model was applied to investigate item fit, ordering of the item response functions, dimensionality and hierarchy of the tests.
  
  
  
  The majority of persons with neck pain had moderate disabilities and the mean value in the Neck disability index was 10.7. Functioning of the movement control tests to measure the construct "movement control abilities" was adequate for the majority of tests. Three movement control tests showed considerable misfit. Possible explanations were a reactive movement control instead of an active control and a more challenging test position. Test difficulties and person abilities could be estimated for the complete sample. The most difficult test was "sitting rocking forward" (1.13 logits) and the least difficult test was "lifting the right arm" (-1.30 logits). The highest person ability estimate was 3.61 logits indicating that movement control tests are missing to evaluate persons with moderate neck disabilities.
  
  
  
  Modifying the existing set of tests is required to evaluate the complete spectrum of persons with neck pain.
authors.affiliation: University of Applied Sciences and Arts Western Switzerland Valais (HES-SO Valais-Wallis), School of Health Sciences, Leukerbad, Switzerland. Electronic address: martin.sattelmayer@gmail.com.
authors.forename: Martin
authors.initials: M
authors.lastname: Sattelmayer
authors.affiliation: University of Applied Sciences and Arts Western Switzerland Valais (HES-SO Valais-Wallis), School of Health Sciences, Leukerbad, Switzerland. Electronic address: roger.hilfiker@gmail.com.
authors.forename: Roger
authors.initials: R
authors.lastname: Hilfiker
authors.affiliation: Zurich University of Applied Sciences, School of Health Professions, Institute of Physiotherapy, Winterthur, Switzerland. Electronic address: luom@zhaw.ch.
authors.forename: Hannu
authors.initials: H
authors.lastname: Luomajoki
authors.affiliation: University of Applied Sciences and Arts Western Switzerland Valais (HES-SO Valais-Wallis), School of Health Sciences, Leukerbad, Switzerland. Electronic address: simone.elsig@gmail.com.
authors.forename: Simone
authors.initials: S
authors.lastname: Elsig
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D004185:Disability Evaluation; D005260:Female; D064368:Healthy Volunteers / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology*; D019547:Neck Pain / Q000175:diagnosis* / Q000503:physiopathology*; D011594:Psychometrics; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires
keywords: Movement control; Neck pain; Rasch analysis