Appendix E. Health Communication Theories

Extended Parallel Process Model

This theoretical model explains the balance of perceived threat and efficacy, and is important for developing fear management approaches. It stipulates that 1) people must feel like the threat to their health is real and serious, and 2) during this time, people must feel like they can take action to evade the threat.

People’s confidence in their ability to act and in their beliefs about how effective their actions will be must be high. If people are in a state of heightened concern (proportionate to the threat) and high efficacy, they will take steps to minimize the threat. However, if concern is high but efficacy is low, this often leads to denial and beliefs in myths and misconceptions, as was seen early on in the Ebola outbreak.

The Extended Parallel Process Model (EPPM) is especially relevant to risk communication because it analyzes the relevance of efficacy when people are overcome by fear.

High Efficacy  

Belief in effectiveness of solutions and confidence to practice them

Low Efficacy  

Doubts about effectiveness of solutions and one’s ability to practice them

High Threat   

Belief that the threat is harmful and that one is at risk

Danger Control   

People take protective action to avoid or reduce the threat.

Strategy: Provide calls to action

Fear Control   

People are too afraid to act and just try to reduce their fear to make themselves feel psychologically better.

Strategy: Educate about solutions

Low Threat   

Belief that the threat is trivial and that one is not at risk

Lesser Amount of Danger Control   

People know what to do but are not really motivated to do much.

Strategy: Educate about risk

No Response   

People don’t feel at risk and don’t know what to do about it anyway.

Strategy: Educate about risk and about solutions


Social Cognitive Learning Theory

This theory argues that people change their behavior when they believe that the benefit of performing the behavior outweighs the cost. People also change their behavior when they have the confidence and skills to perform the behavior. If people know how to protect themselves from Ebola and believe that carrying out these protective steps will benefit them in the long run they are more likely to adopt these protective behaviors.

People also change behavior when they see other people like them modeling the correct way to perform the behavior and the resulting realistic outcomes.  Different communication approaches, such as entertainment education and reality programming, can promote these model characters, leading to higher levels of confidence and skills for dealing with Ebola.

Diffusion of Innovations

This theoretical model describes how a new idea or positive health behavior (e.g., safe burials) can spread through a community or social structure. This model works best when communicators need to make a quick impact on entire communities and have access to well-respected traditional, religious or community leaders, who can adopt the new idea (e.g., safe burials) and “diffuse” or spread the concept to community members.

Theories used for Ebola communication do not need to be complex but should reflect evidence and specific context of the target population. Risk communication interventions may also use one or a combination of multiple theories as a foundation for its strategies and approaches.


Theory Picker is a useful tool to find the best theory for designing an intervention.

A deeper look at some of the theories and their application can be found in this collection of research briefs.