Cognitions about illness have been identified as contributors to health-related behavior, psychological well-being, and overall health. Several different theories have been developed to explain how cognitions may exert their impact on health outcomes. This article includes three theories: the Health Belief Model (HBM), the Theory of Planned Behavior (TPB), and the Common Sense Model (CSM), with the primary focus on the CSM. The HBM posits that cognitions regarding susceptibility to a health threat, the severity of the threat, and the benefits and costs associated with behavior, will determine whether or not a behavior is performed. In the TPB, behavior is thought to be a consequence of intention to act, which is shaped by attitudes regarding a behavior, subjective norms, and perceived behavioral control. The Common Sense Model (CSM) proposes that individuals form cognitive representations of illness (known as illness perceptions) as well as emotional representations, which are key determinants of coping behaviors to manage the illness. Coping behaviors are theorized to have direct relationships with physical and psychological health outcomes. Cognitive representations encompass perceptions regarding the consequences posed by the illness, its timeline, personal ability to control the illness, whether the illness can be cured or controlled by treatment, and the identity of the illness (including its label and symptoms). Emotional representations reflect feelings such as fear, anger, and depression about the illness. The development of illness representations is influenced by a number of factors, including personal experience, the nature of physical symptoms, personality traits, and the social and cultural context. Illness cognitions can vary considerably between patients and health care professionals. There are a number of methods to assess illness-related cognitions, and increasing evidence that modifying negative or inaccurate cognitions can improve health outcomes.
The common sense model applied to hepatitis C: a qualitative analysis of the impact of disease comparison and witnessed death on hepatitis C illness perception
