title: Clinical tests for the evaluation of postural instability in patients with parkinson's disease.
abstract: OBJECTIVE
  To determine which test for postural instability in Parkinson's disease (PD) is reliable, valid, and easy to perform in a clinical setting.
  
  
  METHODS
  Cross-sectional reliability and validity study.
  
  
  METHODS
  Academic center for movement disorders.
  
  
  METHODS
  Forty-two patients with PD and 15 controls. Based on the results of a structured interview, the patients were divided in PD-unstable (n=22) and PD-stable (n=20) groups.
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  Several variants of the retropulsion test with differences in execution and scoring. Responses were scored on 5 different rating scales (ratings of Nutt, Bloem, Pastor; the Unified Parkinson's Disease Rating Scale [UPDRS]; the Short Parkinson Evaluation Scale). These tests were compared with steady-stance positions.
  
  
  RESULTS
  The interrater reliability was high for most ratings, with weighted kappa ranging from.63 for the UPDRS to.98 for both the Pastor rating and steady-stance positions. Most ratings distinguished between the groups. However, the Nutt rating had the highest overall predictive accuracy, with a sensitivity of.63 and a specificity of.88.
  
  
  CONCLUSIONS
  The most valid test for postural stability in PD was an unexpected shoulder pull, executed once, with taking more than 2 steps backward considered abnormal. This retropulsion test is easy to use in a clinical setting.
authors.affiliation: Departmentof Neurology, Leiden University Medical Center, The Netherlands. m.visser@lumc.nl
authors.forename: Martine
authors.initials: M
authors.lastname: Visser
authors.forename: Johan
authors.initials: J
authors.lastname: Marinus
authors.forename: Bastiaan R
authors.initials: BR
authors.lastname: Bloem
authors.forename: Hannah
authors.initials: H
authors.lastname: Kisjes
authors.forename: Barbara M
authors.initials: BM
authors.lastname: van den Berg
authors.forename: Jacobus J
authors.initials: JJ
authors.lastname: van Hilten
mesh_terms: D000058:Accidental Falls / Q000706:statistics & numerical data; D000368:Aged; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000145:classification* / Q000503:physiopathology / Q000534:rehabilitation; D004856:Postural Balance; D011187:Posture; D015203:Reproducibility of Results