The Health Belief Model explains health behaviours through perceived threat and personal efficacy
Perceived susceptibility is your belief about whether you are at risk for a health problem.
Perceived severity is your belief about how serious the health problem would be if you got it.
Perceived benefits is your belief that the recommended action will reduce risk.
Perceived barriers are obstacles that prevent behaviour change, including cost, inconvenience, and side effects.
Cues to action are internal (symptoms) or external (health campaigns, social influence) triggers that prompt behaviour change.
Common Mistake
The Health Belief Model assumes people make rational decisions based on beliefs, but health decisions are often irrational, habitual, or driven by emotions rather than logical cost-benefit analysis.
Example
Someone might avoid vaccinations despite high perceived severity because perceived barriers (fear of needles, inconvenience, belief in side effects) outweigh perceived benefits.
Locus of control shapes whether you believe your health is within your power
Internal locus of control is the belief that your health is controllable through personal actions, predicting preventive behaviours, medication adherence, and better disease management.
External locus of control is the belief that health is determined by fate, luck, or physicians, predicting poorer engagement in health behaviours and worse outcomes.
Health locus of control is the domain-specific version of locus of control; Wallston et al.'s Multidimensional Health Locus of Control Scale shows internal health locus predicts exercise frequency, stress management, and disease prevention.
Note
People with external locus of control are more likely to smoke, drink excessively, and neglect preventive care because they feel powerless to change health outcomes.
Self-efficacy is your confidence in your ability to perform health behaviours
Bandura's self-efficacy concept describes your belief in your ability to execute actions necessary to achieve desired health outcomes.
High self-efficacy for exercise predicts exercise adherence, and high self-efficacy for smoking cessation predicts successful quitting.
Self-efficacy is built through mastery experiences (past successes), observing others succeed (modelling), verbal persuasion (encouragement), and managing physiological arousal (managing stress).
Analogy
Self-efficacy is like an athlete's confidence before competition: high belief in ability predicts better performance than low confidence, even with identical physical training.
Dispositional factors interact to determine health behaviour change
High threat perception (believing health threat is serious and likely) motivates behaviour only if self-efficacy is high and perceived barriers are low.
Internal locus of control strengthens the link between health beliefs and behaviour by increasing the likelihood people act on perceived threats and benefits.
Without self-efficacy, high threat perception and internal locus of control fail to sustain behaviour change in dieting, exercise, and medication adherence.
## Optimism bias affects how people assess health risk
Optimism bias is the tendency to believe negative health outcomes are less likely to happen to you than to others, reducing perceived susceptibility and decreasing preventive behaviour.
Conversely, unrealistic pessimism can lead to anxiety and avoidance behaviours that paradoxically worsen health outcomes.
Note
Cognitive approach: Health beliefs function as information processing filters that guide behaviour decisions.
Biological approach: Dispositional traits like locus of control and optimism may have genetic contributions that influence health behaviour predispositions.
Sociocultural approach: Cultural values, family norms, and socioeconomic factors shape which health beliefs people hold and how they act on them.
Active recall
List the five main components of the Health Belief Model and explain why perceived barriers can override high threat perception.
Distinguish between internal and external locus of control and explain how health locus of control differs from general locus of control.
Describe the four sources of self-efficacy and explain why self-efficacy is sometimes more predictive of behaviour change success than threat perception alone.
Explain how optimism bias affects health decision-making and why rational models like the HBM cannot fully account for health behaviour.
Analyse how internal locus of control, high self-efficacy, and low perceived barriers work together to support sustained health behaviour change.
