EPPM

The Extended Parallel Process Model (EPPM) is a theory in health communication that explains how people respond to fear-based or threat-oriented messages. Developed by Kim Witte in the 1990s, it proposes that responses to risk claims depend on how individuals appraise both the threat and their ability to cope with it.

Perceived threat in the EPPM comprises two components: perceived severity (how serious the threat is) and perceived susceptibility (how likely one is to experience it). Perceived efficacy also has two components: self-efficacy (confidence in one’s own ability to perform the recommended action) and response efficacy (belief that the recommended action will effectively mitigate the threat).

Processing outcomes depend on the interaction of threat and efficacy. If threat is perceived as high and efficacy is high, individuals engage in danger control, adopting protective actions to reduce risk. If threat is high but efficacy is low, fear control processes may dominate, leading to defensive reactions such as denial, avoidance, or message discounting. If threat is perceived as low, motivation to act tends to be minimal, regardless of efficacy.

Applications of the EPPM include the design of health risk communications, where messages aim to raise awareness of a threat while also enhancing efficacy cues so audiences can adopt recommended behaviors. It has been used in campaigns related to smoking cessation, vaccination, sexual health, and emergency preparedness. Critiques note challenges in reliably measuring threat and efficacy constructs, cultural and contextual variability, and mixed empirical support in some domains. Despite criticisms, the model remains a commonly cited framework for understanding when fear appeals will motivate action versus backfire.