The development and testing of an instrument to measure self-efficacy in individuals with epilepsy.

The purpose of this study was to develop and test an instrument to measure self-efficacy in persons with epilepsy. With Bandura's self-efficacy theory serving as the conceptual basis for instrument development, the study was divided into two phases, an instrument development phase and a reliability and validity assessment phase. In phase one, self-efficacy and epilepsy literature along with discussions with epilepsy patients served as sources for item derivation. A panel of experts reviewed the instrument for content validity. In phase two, testing of the instrument for reliability and validity was done using different groups of epilepsy patients. Reliability coefficients ranged from .81 for test-retest reliability to .93 for internal consistency. A strong positive correlation between self-efficacy and social support (r = .48, p less than .001) and between self-efficacy and self-management (r = .50, p less than .001) provided evidence to support the construct validity of the instrument.