Defining child health in the 21st century.

The concept of child health has evolved over many decades and has gone from defining health as the absence of disease and disability to a much more sophisticated understanding of the ways in which a confluence of many factors leads to a healthy childhood and to producing the infrastructure for a healthy lifetime. We review the evolution of these ideas and endorse the definition featured in Children's Health, the Nation's Wealth, which states that child health is: "… the extent to which individual children or groups of children are able or enabled to: (a) develop and realize their potential, (b) satisfy their needs, and (c) develop the capacities that allow them to interact successfully with their biological, physical, and social environments." IMPACT: The definition of child health and the model presented form a framework for conducting and interpreting research in child health and understanding the ways in which influences affect child health. They also demonstrate how child health is the foundation for life-long health. Child health is dynamic and is always changing. There are many influences affecting child health at any given time. Because each child's health is different, they may react in distinctive ways to a new health challenge.