title: Psychometric properties of the Dependence Scale in large randomized clinical trials of patients with mild and moderate Alzheimer's disease.
abstract: OBJECTIVE
  The need for assistance from others is a hallmark concern in Alzheimer's disease (AD). The psychometric properties of the Dependence Scale (DS) for measuring treatment benefit were investigated in large randomized clinical trials of patients with mild to moderate AD.
  
  
  METHODS
  Reliability, validity, and responsiveness of the DS were examined. Path models appraised relationships and distinctiveness of key AD measures. The responder definition was empirically derived.
  
  
  RESULTS
  Generally acceptable reliability (α ≥ .65), significant (P < .001) known-groups tests, and moderate to strong correlations (r ≥ .31) confirmed the DS psychometric properties. Path models supported relationships and distinctiveness of key AD measures. A DS change of ≤ 1 point for patients with limited home care and ≤ 2 points for patients with assisted living care best described stability of the level of dependence on caregivers.
  
  
  CONCLUSIONS
  The DS is a psychometrically robust measure in mild to moderate AD. The empirically derived responder definition aids in the interpretation of DS change.
authors.affiliation: Evidera (formerly United BioSource Corporation), Bethesda, MD, USA kathy.wyrwich@evidera.com.
authors.forename: Kathleen W
authors.initials: KW
authors.lastname: Wyrwich
authors.affiliation: Evidera (formerly United BioSource Corporation), Bethesda, MD, USA.
authors.forename: Priscilla
authors.initials: P
authors.lastname: Auguste
authors.affiliation: Janssen Alzheimer Immunotherapy, San Francisco, CA, USA.
authors.forename: Jacqui
authors.initials: J
authors.lastname: Buchanan
authors.affiliation: Pfizer Patient-Reported Outcomes Centre of Excellence, Surrey, United Kingdom.
authors.forename: Katja
authors.initials: K
authors.lastname: Rudell
authors.affiliation: Janssen Alzheimer Immunotherapy, San Francisco, CA, USA.
authors.forename: Loretto
authors.initials: L
authors.lastname: Lacey
authors.affiliation: Janssen Alzheimer Immunotherapy, San Francisco, CA, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Leibman
authors.affiliation: Pfizer Patient-Reported Outcomes Centre of Excellence, Surrey, United Kingdom.
authors.forename: Tara
authors.initials: T
authors.lastname: Symonds
authors.affiliation: Janssen Alzheimer Immunotherapy, San Francisco, CA, USA.
authors.forename: H Robert
authors.initials: HR
authors.lastname: Brashear
mesh_terms: D000203:Activities of Daily Living / Q000523:psychology*; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000188:drug therapy / Q000473:pathology / Q000523:psychology*; D061067:Antibodies, Monoclonal, Humanized / Q000627:therapeutic use; D003430:Cross-Sectional Studies; D004185:Disability Evaluation; D004311:Double-Blind Method; D005260:Female; D015577:Geriatric Assessment; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D011594:Psychometrics; D015203:Reproducibility of Results; D016896:Treatment Outcome
chemical_list: D061067:Antibodies, Monoclonal, Humanized; C545458:bapineuzumab
keywords: Alzheimer’s disease; caregiver; dependence; interpretation; psychometric properties; responder definition
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