Throughout the report, the committee uses three terms—health, health care, and health care system—that are used routinely by policy makers, legislators, health care organizations, health professionals, the media, and the public. While these terms are commonly used, the definitions can vary and are often nuanced. In this section, the committee offers its definitions for these three core terms. In addition to the terms discussed below, other important terms are defined throughout the report in conjunction with relevant discussion. For example, value and primary care are defined and discussed in Chapter 2.

In a previous Institute of Medicine (IOM) report, “health” is defined as “a state of well-being and the capability to function in the face of changing circumstances.” It is “a positive concept emphasizing social and personal resources as well as physical capabilities” (IOM, 1997). Improving health is a shared responsibility of society, communities, health care providers, family, and individuals. Certain social determinants of health—such as income, education, family, and community—play a greater role than mere access to biomedical care in improving health outcomes for large populations (Commission on Social Determinants of Health, 2008; IOM, 1997). However, access to primary care, in contrast to specialty care, is associated with better population health outcomes (Starfield et al., 2005).

“Health care” can be defined as the prevention, diagnosis, treatment, and management of disease and illness through a wide range of services provided by health professionals. These services are supplemented by the efforts of private individuals (patients), their families, and communities to achieve optimal mental and physical health and wellness throughout life. The committee considers the full range of services to be encompassed by the term “health care,” including prevention and health promotion, mental and behavioral health, and primary care services; public health; acute care; chronic disease management; transitional care; long-term care; palliative care; end-of-life care; and other specialty health care services.