Outcome expectancies as a mediator in the relation of self-efficacy with medication adherence and transition readiness in adolescents and young adults with epilepsy

Objective: About 30% of youth with epilepsy experience seizures into adulthood, making a successful transition from pediatric to adult healthcare paramount for positive health outcomes. Social cognitive theory highlights two targetable factors influencing health behaviors: self-efficacy and outcome expectancies. While self-efficacy is a well-established determinant of health behaviors, the role of outcome expectancies is less understood. The present study investigated outcome expectancies as a potential mediator in the relation between self-efficacy and treatment adherence, as well as adherence in a sample of youth and young adults (AYA) with epilepsy. Method: Data from 46 AYA (ages 14-21) were analyzed. Participants were recruited at routine neurology and neuropsychology appointments and via flyers distributed through an Epilepsy Foundation listserv. AYA completed self-report, validated measures assessing adherence, transition of care, self-efficacy, and outcome expectancies. Two separate mediation analyses were conducted using PROCESS macro version 4.0 (Hayes, 2022) to examine the indirect effects of self-efficacy on (1) transition readiness and (2) adherence, controlling for age. Bootstrapped 95% confidence intervals were used to test the significance of the indirect effects. Results: There was a significant association between self-efficacy and outcome expectancies (a=.01, 95% CI [.00, .01]). Outcome expectancies were not significantly related to adherence (b =.32, 95% CI [-1.44, 2.08]) but were significantly related to transition readiness (b =.34, 95% CI [.06, .63]). There was a total effect of self-efficacy on transition readiness (c=.01, 95% CI [.00, .01]), but no direct effect (c’=.00, 95% CI [-.00, .01]). However, there was a direct effect of self-efficacy on adherence (c’=.04, 95% CI [.01, .07]). Outcome expectancies fully mediated the relation between self-efficacy and transition readiness (a*b=.00, 95% CI [.00, .01]). but not adherence (a*b=.00, 95% CI [-.02, .01]). Conclusion: These findings suggest that self-efficacy influences transition readiness entirely through its impact on outcome expectancies. Thus, AYA confidence in epilepsy management may foster better outcome expectancies if they can manage their seizures, which then promotes greater transition readiness.