Determinants of physical health in frail older people: the importance of self-efficacy.
OBJECTIVE
There is continued uncertainty regarding the strength of association between performance-based and self-report measures of physical functioning, and of their relationship to self-efficacy and health-related quality of life (HRQoL). This study assessed the inter-relationships between such measures, and the predictors of 'physical' aspects of HRQoL in frail older patients.


METHODS
We used statistical models to determine the predictors of 'physical' HRQoL, according to the physical component summary score and the physical functioning domain of the 36-item short form (SF-36) questionnaire.


METHODS
Patients were recruited from hospitals in Australia and New Zealand and followed up in their homes.


METHODS
Two hundred and forty-three frail older patients.


METHODS
Physical functioning was assessed using three performance-based measures (Timed Up and Go Test, gait speed and the Berg Balance Scale) and five self-report measures, including the modified falls self-efficacy scale, at three and six months after registration.


RESULTS
A moderate association (r = 0.48-0.55) was found between each of the performance-based and self-report measures, including the SF-36 physical component summary score. Multiple linear regression analyses showed that the performance-based measures and falls self-efficacy predicted 33% of the SF-36 physical component summary score. Falls self-efficacy was the single highest predictor of both the SF-36 physical component summary score and SF-36 physical functioning domain. A curvilinear relationship was found between the SF-36 physical functioning domain and two variables: falls self-efficacy and the Berg Balance Scale.


CONCLUSIONS
Although performance-based and self-report measures provide complementary but distinct measures of physical function, psychosocial factors such as self-efficacy have a strong influence on the HRQoL of frail older people.
Stretton
Caroline M
CM
School of Physiotherapy, Auckland University of Technology, New Zealand.
Latham
Nancy K
NK
Carter
Kristie N
KN
Lee
Arier C
AC
Anderson
Craig S
CS
D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D016330:Frail Elderly; D006304:Health Status; D006801:Humans; D008297:Male; D015233:Models, Statistical; D011788:Quality of Life; D020377:Self Efficacy