Reliability and validity testing of the short self-efficacy and outcome expectation for exercise scales in stroke survivors

J Stroke Cerebrovasc Dis. Sep-Oct 2004;13(5):214-9. doi: 10.1016/j.jstrokecerebrovasdis.2004.07.002.

Abstract

Self-efficacy has been noted to have a significant impact on exercise behaviors across several clinical conditions, but the influence of self-efficacy and outcome expectations on exercise behaviors in stroke survivors is unknown. This study investigates the reliability and validity of the Short Self-Efficacy for Exercise (SSEE) and Short Outcome Expectations for Exercise (SOEE) scales in stroke survivors and their relationship to regular exercise. A total of 1200 surveys were mailed to stroke support groups throughout North America, with 211 respondents reporting an average age of 66 years and a mean time from stroke of 5.8 years. There was evidence for internal consistency with alpha coefficients of .86 for the SSEE and .90 for the SOEE. Reliability was also estimated using structural equation modeling, and a squared multiple correlation coefficient (R(2)) was used as the estimate of reliability. R(2) values ranged from .38 to .70 in the SSEE and from .47 to .78 in the SOEE. There was evidence of construct validity based on significant lambda values for all items onto their respective constructs. Likewise, there was evidence of construct validity of the SSEE and the SOEE; self-efficacy expectations significantly influenced exercise and accounted for 13% of the variance in exercise, and outcome expectations explained an additional 2% of the variance in exercise, supporting that the SOEE and the SSEE are reliable and valid scales. Measuring these expectations related to exercise post-stroke can establish their influence on exercise behavior and lead to interventions to strengthen these beliefs and improve exercise behavior.