Self-Identity and the Theory of Planned Behavior in the Prediction of Health Behavior and Leisure Activity

To compare the predictive power of an expanded model of the Theory of Planned Behavior (TPB) with that of the original TPB, two studies were conducted in which, in addition to the classical variables of the TPB model (such as attitudes, subjective norms, and perceived behavioral control), variables concerning self-identity were also taken into account. Two independent samples of Italian subjects (N-1 = 288, N-2 = 188) were recruited to study behavioral intentions concerning the domains of leisure activity (attending Latin American dance classes) and health behavior (purchasing of low-fat food) in relation to variables derived from the TPB and from the Identity Theory. Structural equation modeling showed that identity variables contributed significantly and independently to the explanation of behavioral intentions beyond traditional TPB variables.