title: Psychometric performance of an assessment scale for strain in nursing care: the M-NCAS.
abstract: BACKGROUND
  Multiple instruments exist to measure dementia behaviors, but the nursing staff perspective on those behaviors and their level of burden has not been well measured. The goal of this study was to examine the psychometric performance of the Modified Nursing Care Assessment Scale (M-NCAS), a 28-item nurse rating of burden associated with care for institutionalized individuals with dementia. Nurses rate items in terms of extent to which the behavior or characteristic is present ("attitude" domain), and extent to which it is a burden ("strain" domain).
  
  
  METHODS
  Data from 282 patients enrolled in a 12-week, double-blind, randomized clinical trial comparing risperidone treatment to placebo was used to evaluate M-NCAS item performance, internal consistency reliability, and construct validity. Empirical subscales were identified via exploratory factor analysis (EFA).
  
  
  RESULTS
  Four poorly-performing items were deleted from further analyses. EFA identified 3 "attitude" subscales and 5 "strain" subscales. Cronbach's alphas were 0.65 and above. Correlation with the Cohen-Mansfield Agitation Inventory and the BEHAVE-AD, clinical ratings of dementia behaviors, were low to moderate.
  
  
  CONCLUSIONS
  The M-NCAS provides a valid and reliable means of obtaining care burden ratings from formal caregivers in long-term care, and provides a method for evaluating dementia interventions from the perspective of nursing staff.
authors.affiliation: MEDTAP International, Inc,, 2601 4th Ave, Seattle, WA 98121, USA. kleinman@medtap.com
authors.forename: Leah
authors.initials: L
authors.lastname: Kleinman
authors.forename: Lori
authors.initials: L
authors.lastname: Frank
authors.forename: Gabrielle
authors.initials: G
authors.lastname: Ciesla
authors.forename: Marcia
authors.initials: M
authors.lastname: Rupnow
authors.forename: Henry
authors.initials: H
authors.lastname: Brodaty
mesh_terms: D000368:Aged; D000374:Aggression / Q000523:psychology; D000544:Alzheimer Disease / Q000188:drug therapy / Q000451:nursing* / Q000523:psychology*; D001315:Australia; D015140:Dementia, Vascular / Q000188:drug therapy / Q000451:nursing* / Q000523:psychology*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008134:Long-Term Care / Q000523:psychology*; D008297:Male; D008875:Middle Aged; D009520:New Zealand; D009723:Nurse-Patient Relations; D009730:Nursing Assessment / Q000379:methods*; D009735:Nursing Homes; D009740:Nursing Staff / Q000523:psychology*; D010919:Placebos; D011569:Psychiatric Status Rating Scales; D011594:Psychometrics / Q000295:instrumentation*; D011595:Psychomotor Agitation / Q000523:psychology; D018967:Risperidone / Q000627:therapeutic use; D018434:Sickness Impact Profile
chemical_list: D010919:Placebos; D018967:Risperidone