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Published on: July 27, 2018
Concordance of proxy-perceived change and measured change in multiple domains of function in older persons
Nobufumi Yasuda1, Sheryl Zimmerman, William G Hawkes
1Department of Public Health, Kochi Medical School, Kochi, Japan. yasudan@med.kochi-ms.ac.jp
Objectives:
To compare proxy perceptions about change over 6 months in physical, instrumental, affective, and cognitive functioning of older persons with computed change in patient self-report and performance and patient's own perceptions about change.
Design:
Prospective study.
Setting:
Recovery from hip fracture that occurred in community-dwelling persons in Baltimore, Maryland, in 1990-91. The recovery from the sixth to the 12th month postfracture was observed.
Participants:
One hundred forty-one hip fracture patients aged 65 and older and a self-designated proxy for each.
Measurements:
For specific tasks of physical and instrumental functioning, proxy perception of change over the previous 6 months asked in the 12th month postfracture was compared with change in criterion measures (subject self-report and observed performance) from the sixth to the 12th month postfracture. For global change over the previous 6 months in each area of functioning, proxy perception was compared with the subject's own perception in the 12th month postfracture.
Results:
Agreement between proxy perceptions of change and change in criterion measures was poor. There was a general pattern for proxies to overstate improvement and understate deterioration in comparison with change observed in criterion measures for specific tasks of physical and instrumental functioning. Proxies' global perceptions reported subjects improving less and deteriorating more than patients' own perceptions.
Conclusion:
Proxy perceptions about task-specific and global changes in subjects' functional health over a short period of time are systematically different from patient report and observed performance.
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