Which model states that intention is the main predictor of health behavior?

The Theory of Planned Behavior is centered around the idea that individual intentions are the primary predictors of health behavior. This model operates on the premise that a person's intention to engage in a specific behavior is influenced by three key factors: their attitude toward the behavior, the subjective norms surrounding that behavior, and their perceived behavioral control.

By focusing on intention, the theory effectively captures the motivational aspect of behavior change, emphasizing that strong intentions typically lead to a higher likelihood of action. For instance, if someone believes that exercising is beneficial (positive attitude), feels social pressure to exercise (subjective norm), and believes they have the ability to exercise regularly (perceived behavioral control), they are much more likely to follow through with the behavior.

Other models such as the Diffusion of Innovation Theory focus on how new ideas are spread through cultures, the Social Cognitive Theory emphasizes the role of observational learning and self-efficacy, and the Transtheoretical Model outlines stages of change, rather than specifically centering on intention as the key predictor of health behaviors. This highlights the unique and crucial role that intention plays in the Theory of Planned Behavior compared to the other models.