Individual-level theories explain why people make health decisions. The Health Belief Model focuses on perceptions of risk and benefits, while the Theory of Planned Behavior considers attitudes, social norms, and perceived control.

These models help us understand what drives health behaviors. By looking at personal beliefs and intentions, we can predict and influence choices people make about their health and well-being.

Health Belief Model

Key Components of the Health Belief Model

• Health Belief Model (HBM) is a psychological model that attempts to explain and predict health behaviors by focusing on the attitudes and beliefs of individuals
• Developed in the 1950s by social psychologists at the U.S. Public Health Service to understand the failure of people to adopt disease prevention strategies or screening tests for the early detection of disease
• Suggests that a person's belief in a personal threat of an illness or disease together with a person's belief in the effectiveness of the recommended health behavior or action will predict the likelihood the person will adopt the behavior

Perceptions Influencing Health Behavior

• Perceived susceptibility refers to a person's subjective perception of the risk of acquiring an illness or disease
  • People with low perceived susceptibility may deny that they are at risk for contracting a particular illness
  • Individuals who believe they are at low risk of developing an illness are more likely to engage in unhealthy, or risky, behaviors
• Perceived severity is a person's feelings on the seriousness of contracting an illness or disease (or leaving the illness or disease untreated)
  • Feelings related to the consequences of an illness or disease (e.g., death, disability, and pain)
  • Medical consequences (e.g., death, disability) and social consequences (e.g., effects of the conditions on work, family life, and social relations)
• Perceived benefits refer to an individual's perception of the effectiveness of various actions available to reduce the threat of illness or disease (or to cure illness or disease)
  • Course of action a person takes in preventing or curing illness or disease relies on consideration and evaluation of both perceived susceptibility and perceived benefit, such that the person would accept the recommended health action if it was perceived as beneficial
• Perceived barriers are an individual's feelings on the obstacles to performing a recommended health action
  • Relates to the potential negative aspects of a particular health action (e.g. expensive, dangerous, unpleasant, inconvenient, time-consuming) that may act as impediments to undertaking the recommended behavior

Additional Factors Influencing Health Behavior

• Cues to action are events, either bodily (e.g., physical symptoms of a health condition) or environmental (e.g., media publicity) that motivate people to take action
  • Provide how-to information, promote awareness, and employ reminder systems to trigger engagement in health-promoting behaviors
• Self-efficacy is the level of a person's confidence in his or her ability to successfully perform a behavior
  • Influences the adoption of healthy behaviors, cessation of unhealthy behaviors, and maintenance of behavioral changes
  • Developed by Albert Bandura as part of his Social Cognitive Theory

Theory of Planned Behavior

Key Components of the Theory of Planned Behavior

• Theory of Planned Behavior (TPB) is a theory that links one's beliefs and behavior
• Proposes that an individual's intention to perform a behavior is the proximal predictor of behavior
• Behavioral intention is influenced by a person's attitude toward performing the behavior, the subjective norms, and the perceived behavioral control
• Developed by Icek Ajzen as an extension of the Theory of Reasoned Action to account for conditions where individuals do not have complete volitional control over a behavior

Factors Influencing Behavioral Intention

• Attitudes are an individual's overall evaluation of the behavior
  • Involves an individual's beliefs about the outcomes or attributes of performing the behavior (behavioral beliefs)
  • Attitudes are typically measured using bipolar scales (e.g., harmful-beneficial, pleasant-unpleasant, good-bad)
• Subjective norms refer to an individual's perception of whether people important to the individual think the behavior should be performed
  • Measured by asking respondents to indicate whether important referent individuals would approve or disapprove of their performing a given behavior
• Perceived behavioral control refers to an individual's perceptions of their ability to perform a given behavior
  • Encompasses the perceived ease or difficulty of performing the behavior of interest in light of past experiences and anticipated obstacles
  • When people believe that they have the resources and opportunities to perform the behavior, and that the behavior is not difficult to perform, they should have confidence in their ability to perform it and thus have a high degree of perceived behavioral control