Determinants of self efficacy for physical tasks in people with knee osteoarthritis
Article first published online: 6 FEB 2006
Copyright © 2006 by the American College of Rheumatology
Arthritis Care & Research
Volume 55, Issue 1, pages 94–101, 15 February 2006
How to Cite
Maly, M. R., Costigan, P. A. and Olney, S. J. (2006), Determinants of self efficacy for physical tasks in people with knee osteoarthritis. Arthritis & Rheumatism, 55: 94–101. doi: 10.1002/art.21701
- Issue published online: 6 FEB 2006
- Article first published online: 6 FEB 2006
- Manuscript Accepted: 18 AUG 2005
- Manuscript Received: 4 MAY 2005
- Canadian Institutes for Health Research. Grant Number: 99034
- Toronto Rehabilitation Institute
- Natural Sciences and Engineering Research Council of Canada
- Outcome assessment;
Self efficacy, the confidence an individual has to perform a task, is an important determinant of physical performance in individuals with knee osteoarthritis (OA). The purpose of this study was to determine what personal, pathophysiologic, and impairment factors relate to self efficacy for physical tasks in community-dwelling adults with knee OA.
Fifty-four persons with radiographically confirmed knee OA (mean ± SD age 68.3 ± 8.7 years, range 50–87 years) participated. The Functional Self-Efficacy subscale of the Arthritis Self-Efficacy Scale was the dependent measure. Independent measures included age, education, scores from the Center for Epidemiologic Studies Depression and State-Trait Anxiety Inventory questionnaires, medial joint space and varus/valgus tibiofemoral angle from radiographs, body mass index, and isokinetic quadriceps and hamstrings strength. Knee pain and stiffness, assessed using the Western Ontario and McMaster Universities Osteoarthritis Index, were independent measures.
Fifty-one percent of the variance of Functional Self Efficacy was explained by knee stiffness, hamstrings strength, age, and depression scores. Pain, education, anxiety, radiographic joint space, and body weight did not significantly contribute to the variance in Functional Self-Efficacy scores. Substituting quadriceps strength for hamstrings strength resulted in a regression model that included only stiffness, age, and depression, which explained nearly as much variance as the original model.
Self efficacy for physical tasks is related to the sensation of stiffness, hamstrings strength, age, and level of depressive symptoms in persons with knee OA. Clinicians and researchers could consider these variables when assessing the level of self efficacy for physical tasks in persons with knee OA.