TY - JOUR
T1 - Reliability and sensitivity to change assessed for a summary measure of lower body function
T2 - Results from the Women's Health and Aging Study
AU - Ostir, Glenn V.
AU - Volpato, Stefano
AU - Fried, Linda P.
AU - Chaves, Paulo
AU - Guralnik, Jack M.
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2002/9/1
Y1 - 2002/9/1
N2 - Original Article A summary performance measure comprised of a hierarchical balance task, a 4-meter walk, and five repetitive chair stands is increasingly being used as a predictor of independent living for older persons. The reliability and sensitivity to change of this summary performance measure have not been investigated, however. Because a measure can be reliable while being unresponsive to change, this study presents information on both the reliability and sensitivity to change for the summary performance measure. This is a 3-year prospective cohort study of 1,002 moderately to severely disabled older women. Short- and long-term reliability was assessed by intraclass correlation coefficients (ICC). Sensitivity to change was assessed by slope differences for three age categories (65-74, 75-84, and ≥85) over six 6-month follow-up periods. Sensitivity to change was also assessed by summary performance change scores for those who did and did not suffer from one of four medical events [myocardial infarction (MI), stroke, hip fracture, or congestive heart failure (CHF)] at follow-up. The summary performance measure showed excellent reliability. Intraclass correlation coefficients ranged from 0.88 to 0.92 for measures made 1 week apart. The 6-month average intraclass correlation coefficient was 0.77 (range 0.72-0.79). The summary performance measure was also highly responsive to change. Subjects who suffered an incident MI, stroke, hip fracture, or CHF at follow-up were significantly more likely to have poorer summary performance change scores (-2.25) compared with those who did not have one of these medical events (-0.24). Additionally, subjects who suffered one of these events improved their summary performance scores in the following assessment period by 0.72. With increasing utilization of the summary performance measure by researchers and clinicians it is important that the measurement properties of this instrument are known. Our results show that the summary performance measure has excellent reliability and is highly sensitive to change.
AB - Original Article A summary performance measure comprised of a hierarchical balance task, a 4-meter walk, and five repetitive chair stands is increasingly being used as a predictor of independent living for older persons. The reliability and sensitivity to change of this summary performance measure have not been investigated, however. Because a measure can be reliable while being unresponsive to change, this study presents information on both the reliability and sensitivity to change for the summary performance measure. This is a 3-year prospective cohort study of 1,002 moderately to severely disabled older women. Short- and long-term reliability was assessed by intraclass correlation coefficients (ICC). Sensitivity to change was assessed by slope differences for three age categories (65-74, 75-84, and ≥85) over six 6-month follow-up periods. Sensitivity to change was also assessed by summary performance change scores for those who did and did not suffer from one of four medical events [myocardial infarction (MI), stroke, hip fracture, or congestive heart failure (CHF)] at follow-up. The summary performance measure showed excellent reliability. Intraclass correlation coefficients ranged from 0.88 to 0.92 for measures made 1 week apart. The 6-month average intraclass correlation coefficient was 0.77 (range 0.72-0.79). The summary performance measure was also highly responsive to change. Subjects who suffered an incident MI, stroke, hip fracture, or CHF at follow-up were significantly more likely to have poorer summary performance change scores (-2.25) compared with those who did not have one of these medical events (-0.24). Additionally, subjects who suffered one of these events improved their summary performance scores in the following assessment period by 0.72. With increasing utilization of the summary performance measure by researchers and clinicians it is important that the measurement properties of this instrument are known. Our results show that the summary performance measure has excellent reliability and is highly sensitive to change.
KW - Aging
KW - Disability
KW - Reliability
KW - Sensitivity to change
KW - Summary performance measure
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U2 - 10.1016/S0895-4356(02)00436-5
DO - 10.1016/S0895-4356(02)00436-5
M3 - Article
C2 - 12393080
AN - SCOPUS:0036711374
SN - 0895-4356
VL - 55
SP - 916
EP - 921
JO - Journal of Clinical Epidemiology
JF - Journal of Clinical Epidemiology
IS - 9
ER -