ABSTRACT
This chapter examines five theories or models employed by health psychologists to explain a range of health behaviors: expectancy value theory, the theory of planned behavior, the health belief model, social cognitive theory, and the transtheoretical model of behavior change. Expectancy value theory (EVT), the theory of planned behavior (TPB), and the social cognitive theory (SCT) were developed originally to explain general human behavior. The chapter describes social marketing and its contribution to promoting behavior change. It discusses an ecological approach to health by explaining the relative contributions of the individual, cultural or social networks, environment, health systems, and health policy on individual health outcomes. Albert Bandura's theory offers an interesting approach to understanding human behaviors and specifically health behaviors. A model designed to examine the motivational factors specifically associated with health behaviors is the health belief model (HBM).
