Personal models and the management of chronic illness: a comparison of diabetes and osteoarthritis

Personal models of illness are people's beliefs and emotions about their disease. Structured interviews for measuring personal models of diabetes and osteoarthritis were developed that included questions about the symptoms, cause, time line, consequences, and treatment of these diseases. The structure and content of personal models for these diseases were found to differ in ways that reflected the medical differences between the two conditions. Prospective relations between personal models and disease self-management also differed. For diabetes, beliefs about the effectiveness of activities to control blood-glucose levels were most predictive of self-management (particularly following dietary recommendations). For osteoarthritis, beliefs about the intensity of the condition (a combination of symptoms and consequences) was most predictive of self-management. The significance of individual differences on personal models for tailoring interventions, and the place of personal models in social cognition theories of health and of personality, are discussed.