sures to multiple influences over longer time frames. This is well illustrated in how various behavioral influences (e.g., poor diet, lack of exercise) interact with genetic influences to affect the development of obesity and how multiple influences (e.g., genes, exposure to allergens and antigens, family behaviors, physical and social environments, health services) affect the development and severity of childhood asthma (Evans and Stoddart, 1990, 2003).
In the United States, the high cost of chronic conditions and the high proportion of elderly people who have one or more of these conditions have led to a primary focus on these aspects of health. As multiple influences on health became better understood, the notion of health as a positive capacity and a prerequisite for a range of human accomplishment took root, elevating the importance of both disease prevention and health promotion (Breslow, 1999).
Precise definitions of health, emphasizing negative, normative, and positive notions of health, have been debated for centuries (Institute of Medicine, 2001b, p. 21). Over time, there has been growing recognition that health is more than the absence of disease. This concept was most dramatically articulated in 1948 by WHO with the following definition (which remains their current definition): “Health is a state of complete physical, mental, and social well-being, not merely the absence of disease or infirmity.”
Several recent reports from the National Academies have reviewed issues in the definition and measurement of health for various specific purposes. These include studies focused on (a) better understanding of the interplay of biological, behavioral, and social influences on health outcomes (Institute of Medicine, 2001b); (b) improving performance monitoring of community health services (Institute of Medicine, 1997); and (c) defining the future research agenda in the behavioral and social sciences for the National Institutes of Health (National Research Council, 2001). Each of these previous reports, as well as several others, highlights the advantages and disadvantages of various definitions, but in none has the primary focus been directed toward children’s health issues. Each, however, emphasizes the importance of notions of positive health and the interplay of multiple individual and environmental factors.
Many critiques of previous definitions focus on their breadth: what is included and what is excluded. For example, while the WHO’s broad and comprehensive definition of health has been used extensively to exhort and advocate for new health interventions and policies, it has also been criticized as being overly inclusive of all human endeavors and very difficult to apply for the purposes of health measurement (Institute of Medicine, 2001b; Young, 1998; Evans and Stoddardt, 1990). Similarly, while there are advantages to biologically based definitions of health, including the specification of precise biomarkers, such definitions cannot capture all the important and commonly understood components of health, such as the capacity to respond to stress or resist disease.
From a medical perspective, health is still defined largely as freedom from injury, disease, or disability. However, the medical community is increasingly