| The author discusses the results of a research project that examines the structure and content of perceived behavioral control (PBC), one of the three antecedents to behavioral intention in the Theory of Planned Behavior (Ajzen, 1988). Specifically, in the context of physician diagnostic and treatment decisions, the research project examined whether, as Ajzen (2002) argues, PBC is a unitary construct that contains elements of perceived self-efficacy (Bandura, 1995) and perceived controllability, or in the alternative, is better explained as perceived self-efficacy only, with perceived controllability a separate latent variable that moderates the relationship between perceived self-efficacy and physician behavioral intentions.; The research project relied upon a study of physician intentions to use mind-body therapies (MBTs) in connection with their practices and in their self-care. The author used hierarchical multiple regression analysis and sequential discriminant function analysis to demonstrate that the theory of planned behavior offers a predictive advantage over the theory of reasoned action, but more so with regard to the use of MBTs on patients than their use on the physicians themselves. In addition, he also used traditional moderator analysis (Baron & Kenny, 1986) to examine, and reject, a proposed modification to TPB that posits perceived controllability as a moderator variable. The findings that self-efficacy and perceived controllability, taken as separate constructs, seem to explain more variance in physician decision-making than when they are combined to form a single variable suggests that TPB may be in need of revision. |
