title: Patient-caregiver functional unit scale: a new scale to assess the patient-caregiver dyad.
abstract: OBJECTIVE
  This study evaluated the reliability and validity of the Patient-Caregiver Functional Unit Scale (PCFUS), a new instrument to assess the stability or endurance of patient-caregiver dyads.
  
  
  METHODS
  Patient-caregiver dyads were recruited from a nursing home (NH) (n = 38), a comprehensive geriatric assessment program (CGA) (n = 20), and an ambulatory medical clinic (controls) (n = 85). Caregivers were eligible if they assisted, or were available to assist, the patient with personal and instrumental activities of daily living, without pay. Data were collected by interviewer-administered questionnaires. Inter-rater and test-retest reliability were evaluated among the CGA sample. Validity was assessed by comparing PCFUS scores among the NH, CGA, and control groups and by correlation of PCFUS scores with other standardized caregiver burden measures.
  
  
  RESULTS
  The PCFUS had excellent inter-rater and test-retest reliability. Mean PCFUS scores were significantly lower (ie, less stable patient-caregiver dyad) in NH than CGA and control caregivers. PCFUS scores were significantly associated with Burden Interview, Perceived Stress Scale, and Geriatric Depression Scale scores and risk factors for caregiver stress (eg, patient's cognitive impairment, disruptive behaviors).
  
  
  CONCLUSIONS
  The PCFUS is a short, easily administered measure with good reliability and validity and is applicable to clinical and research settings.
authors.affiliation: Department of Epidemiology and Preventive Medicine, University of Maryland, USA. lfredman@epin.ab.umd.edu
authors.forename: L
authors.initials: L
authors.lastname: Fredman
authors.forename: M P
authors.initials: MP
authors.lastname: Daly
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017028:Caregivers; D005260:Female; D015577:Geriatric Assessment; D006801:Humans; D007398:Interpersonal Relations; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D013315:Stress, Psychological