Applying the Extended Theory of Planned Behavior to health behaviors: meta-analysis and empirical test

Abstract

The Extended Theory of Planned Behavior (eTPB) includes sub-components of attitudes (instrumental/affective), norms (injunctive/descriptive) and perceived behavioral control (self-efficacy/perceived control) to predict intentions and action. A meta-analysis (Study 1) and empirical test of the eTPB (Study 2) in relation to health behaviors are reported. In relation to intentions, Study 1 showed self-efficacy and affective attitudes had large, while other constructs had small-medium sized correlations; regressions showed all constructs except perceived control were significant predictors. In Study 2, regressions controlling for past behavior, showed similar patterns. In relation to action, Study 1 showed intentions, self-efficacy and affective attitudes had medium-large, while other constructs had small-medium sized correlations; regressions showed intentions, self-efficacy, affective attitudes and descriptive norms were significant predictors. In Study 2, regressions controlling for past behavior showed intentions, affective attitudes, injunctive norms and descriptive norms (protection behaviors), or intentions, self-efficacy, affective attitude and descriptive norms (risk behaviors), were significant predictors of action. eTPB has utility in predicting health behaviors and suggests novel relationships informing intervention studies.