Which theory adds the concept of self-efficacy to the model of behavior change?

The Theory of Planned Behavior incorporates the concept of self-efficacy into the model of behavior change. This theory expands on the earlier Theory of Reasoned Action by adding the dimension of perceived behavioral control, which reflects an individual's belief in their capability to perform a specific behavior. Self-efficacy, or the belief in one's own abilities to succeed in specific situations, plays a crucial role in influencing the overall intention to engage in a behavior.

This model suggests that behavior is guided by three key components: attitudes toward the behavior, subjective norms, and perceived behavioral control—where self-efficacy is a significant aspect of perceived behavioral control. Therefore, an individual’s confidence in their ability to perform a behavior can strongly affect their intention to engage in that behavior, making it a critical element in understanding how and why individuals change their behaviors.

In contrast, the other models listed do not incorporate self-efficacy as a central component. The Theory of Reasoned Action focuses more on attitudes and norms without addressing perceived control. The Elaboration Likelihood Model and the Heuristic Systematic Model pertain to persuasion and information processing rather than individual behavior change and empowerment through self-belief.