J. Gomar, Philip D. Harvey, M. Bobes-Bascarán
Nov 1, 2011
The American journal of geriatric psychiatry : official journal of the American Association for Geriatric Psychiatry
BACKGROUND Functional capacity includes basic and complex behaviors necessary to independently live in the community. It has been found that patients with cognitive impairment have daily living functional skills altered at very early stages of illness. OBJECTIVES 1) To develop and validate a brief scale derived from the University of California, San Diego, performance-based skills assessment (UPSA); 2) to cross-validate this new UPSA short form with an independent healthy elderly sample. METHOD Fifty-one healthy elderly subjects, 26 mild cognitive impairment (MCI) subjects defined per Petersen's criteria, and 22 probable Alzheimer Disease (AD) subjects according to National Institute of Neurological and Communicative Disorders and Stroke-AD and Related Disorders Association criteria were included. For cross-validation purpose, a comparison group of 108 older healthy subjects with Mini-Mental scores of 25 or greater was also recruited. A modified four-functional domain version of the UPSA was administered. RESULTS Communication and comprehension/planning domains accounted for almost 90% of the variance (R = 0.89) and in all models entered first and second, respectively. An UPSA short form using these two domains was significantly correlated with the full UPSA scale in all the groups examined: 0.86 for healthy controls; 0.87 for MCI; and 0.88 for AD. Acceptable sensitivity and specificity values for the UPSA short form were found in receiver operating characteristic (ROC) analysis. A correlation of 0.80 was found between the short and the full UPSA scales in the cross-validation sample. CONCLUSIONS The UPSA short form is a rapid, reliable, and efficient measure of functional capacity that is able to detect performance impairment in an ecologically valid setting in much less time compared with the extended form of the scale. Furthermore, it demonstrated adequate discriminative properties among healthy subjects, MCI patients, and AD patients.