Moderating role of perceived behavioral control in the theory of planned behavior: A preregistered study

Investigators frequently rely on the theory of planned behavior (TPB) as a conceptual framework to explain and predict human behavior in a variety of behavioral domains. Much of this research has focused on predicting behavioral intentions from attitudes, subjective norms and perceived behavioral control, typically by examining the additive effects of these constructs. However, in the original formulation of the TPB, perceived behavioral control was postulated to moderate the influence of attitude and subjective norm on intention. This tenet of the TPB has been drawing increasing attention in recent years. In a preregistered program of research conducted in two European countries (Germany and UK) concerning two different behaviors (exercising and reducing energy consumption), we found empirical support for the postulated moderating effects. The results suggest that as scores on perceived behavioral control increase, the strength of the association between attitude and intention increases as well, whereas the strength of the association between subjective norm and intention decreases. Implications of these findings for theory and future research are discussed.