title: Functional status after critical illness: agreement between patient and proxy assessments.
abstract: BACKGROUND
  assessment of baseline functional status of older patients during and after intensive care unit (ICU) admission is often hampered by challenges related to the critical illness such as cognitive dysfunction, neuropsychological morbidity and pain. To explore the reliability of assessments by carefully chosen proxies, we designed a discriminating selection of proxies and evaluated agreement between patient and proxy responses by assessing activities of daily living (ADLs) at 1 month post-ICU discharge.
  
  
  METHODS
  patients ≥60 years old admitted to the medical ICU were enrolled in a prospective parent cohort studying delirium. Proxies were carefully screened at ICU admission to choose the best available respondent. Follow-up interviews, including instruments for ADLs, were conducted 1 month after ICU discharge. We examined 179 paired patient-proxy follow-up interviews. Kappa statistics assessed inter-observer agreement, and McNemar's exact test assessed response differences.
  
  
  RESULTS
  patients averaged 73.3 ± 8.1 years old with 29% having evidence of cognitive impairment. Proxies were most commonly spouses (38%) or children (39%). Overall, there was substantial (κ ≥ 0.6) to excellent agreement (κ ≥ 0.8) between patients and proxies on assessment of all but one basic and one instrumental ADL.
  
  
  CONCLUSIONS
  proxies carefully chosen at ICU admission show high levels of inter-observer agreement with older patients when assessing current functional status at 1 month post-ICU discharge. This motivates further study of proxy assessments that could be used earlier in critical illness to assess premorbid functional status.
authors.affiliation: Department of Internal Medicine, Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, PO Box 208057, New Haven, CT, USA.
authors.forename: Amy M
authors.initials: AM
authors.lastname: Ahasic
authors.affiliation: Department of Internal Medicine, Section of Geriatrics, Yale University School of Medicine, New Haven, CT, USA Yale Program on Aging, Yale University School of Medicine, New Haven, CT, USA.
authors.forename: Peter H
authors.initials: PH
authors.lastname: Van Ness
authors.affiliation: Department of Internal Medicine, Section of Geriatrics, Yale University School of Medicine, New Haven, CT, USA Yale Program on Aging, Yale University School of Medicine, New Haven, CT, USA.
authors.forename: Terrence E
authors.initials: TE
authors.lastname: Murphy
authors.affiliation: Department of Internal Medicine, Section of Geriatrics, Yale University School of Medicine, New Haven, CT, USA Yale Program on Aging, Yale University School of Medicine, New Haven, CT, USA.
authors.forename: Katy L B
authors.initials: KL
authors.lastname: Araujo
authors.affiliation: Department of Internal Medicine, Section of Pulmonary, Critical Care and Sleep Medicine, Yale University School of Medicine, PO Box 208057, New Haven, CT, USA.
authors.forename: Margaret A
authors.initials: MA
authors.lastname: Pisani
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D003072:Cognition Disorders / Q000175:diagnosis / Q000453:epidemiology; D016638:Critical Illness / Q000453:epidemiology; D015577:Geriatric Assessment / Q000379:methods / Q000706:statistics & numerical data; D006801:Humans; D007362:Intensive Care Units / Q000706:statistics & numerical data; D007407:Interviews as Topic; D008875:Middle Aged; D015588:Observer Variation; D010351:Patient Discharge / Q000706:statistics & numerical data; D011446:Prospective Studies; D019727:Proxy / Q000706:statistics & numerical data; D015203:Reproducibility of Results; D012647:Self-Assessment
keywords: activities of daily living; critical care; epidemiologic methods; older people; proxy