Children

The committee adopted the term “children” to refer to groups of individuals from the time of birth to their 18th birthday. Surveys and other data sources employ differing age ranges, and the committee recognizes that, from a developmental perspective, there is no exact age at which childhood definitively ends. Numerous factors can affect the timing of one’s transition from adolescence to adulthood and, as a result, individuals transition from child to adult roles at different rates. For some, adult roles are assumed during adolescence, while for others this does not occur until the middle of the third decade of life. Nevertheless, many datasets and systems consider individuals before and after they reach legal majority, so the committee has chosen age 18 as a minimum age for ending childhood. However, while the committee asserts that data on children’s health should extend at least to that point, collection of data for those older than 18 should be an important data collection priority for the nation. The committee also recognizes that myriad factors affect the developing fetus prior to birth that impinge on and influence the health of children at birth. In this report these prenatal factors are considered and discussed as influences on children’s health.

Although the terms “youth” or “adolescents” are often used to refer to older children and the terms “infants” and “toddlers” refer to very young children, for ease of reference, this report uses the term “children” to encompass all these groups. If a statement is intended to refer to a subset of the child population (e.g., infants, adolescents) the relevant descriptive term is used in the text.

Children’s Health, Safety, and Well-Being

The committee was asked to assess definitions of health and questions related to children’s health, safety, and well-being. This section provides a brief overview of the committee’s approach to children’s health and outlines how safety and well-being were considered in the report. Chapter 2 discusses these issues in more detail.

Health: Most available definitions or conceptualizations of health have been developed for adults. In the committee’s view, these approaches do not account for issues particularly salient for children and do not reasonably transfer to children’s health. Definitions of children’s health must account for their special characteristics, particularly rapid development during childhood. They also must consider multiple influences that interact over time in different ways as children develop and change. The committee proposes a new definition of children’s health that embraces health conditions, functioning, and health potential in a new conceptual model that considers multiple interrelated factors as influences.

Safety: Safety generally refers to aspects of the environment that contribute to health, including the physical environment (e.g., absence of toxins or pollutants in ground water, use of car seats and bicycle helmets), social environment (e.g., low neighborhood crime rates, low rates of risky behaviors either by the children or adults), and psychological environment (e.g., the perception of not being in personal danger). Some environmental and behavioral influences might be conceptualized as contributing to less safe situations, while others might be viewed as health-promoting, safety-related, or protective.

At any given moment in time, children are exposed to a range of risk and protective influences. To the extent that one or the other predominates (assuming this could be determined), it may be possible to characterize children’s social or biological environments as relatively safer, health-promoting, or risky. More often it is possible to characterize an environment as risky or safe with respect to a single influence or single set of variables. Such factors can be used to make statements about the likely current or future health of a given population and, in effect, are often used as “proxies” for the actual health of a given population. In this report, children’s safety is considered to be those influences that result in an environment that contributes positively to health and is discussed primarily in Chapter 3.

Well-Being: Well-being is commonly considered to be the sense of self as appraised by the individual. Concepts such as quality of life, fulfillment, and ability to contribute constructively to society and one’s own family are important aspects of well-being. Well-being inherently involves comparisons with how one feels one should be, given one’s age, preexisting health status or the health status of other persons in the social network, and physical status. For example, some children with attention deficit disorder and asthma that is controlled by medication, who are able to participate in a range of extracurricular activities and have many friends, may perceive themselves as healthy and fortunate, whereas others may not. Or children with no obvious physical illness but a subjective sense of poor well-being might be conceived to be in good physical health but potentially in compromised psychological health or in physical peril. Thus, one’s sense of well-being is an important component of overall health that has been shown to affect one’s overall functioning and prognosis, at least in adult health (Berkman and Syme, 1979).

In the developmental literature, well-being is often considered to be a state broader than health that incorporates social, psychological, educational, behavioral, and economic dimensions. The term “health and well-being” is used to recognize that aspects of children’s life beyond traditional health considerations are important to both their current condition and to their future potential as adults, as well as to capture positive aspects of health. The committee contends that behavioral, psychological, and social well-being are core aspects of health and has incorporated these within the domain of health termed “health potential,” discussed in the next chapter. As used in this report, the term “health” therefore inherently embraces health-related aspects of well-being.

Risk, Protective, and Promotional Factors (Influences on Children’s Health)

A multitude of biological, behavioral, and environmental factors can either pose a risk to children’s health or act in a protective or health-promoting capacity. For example, children’s social environments can be characterized by a number of influences that can be viewed as safe, health-promoting, risky, or detrimental. Many factors (e.g., peers) can be either a risk to health or a protective factor, depending on the specific circumstances. Given this uncertainty, the committee adopted the term “influences on children’s health” to refer to risk, protective, and promotional factors.

The distinction between health and influences on health is usually straightforward. In a few instances, however, the distinction is ambiguous. For example, risk behaviors are considered an influence in this report, although a strong case could be made that daily alcohol use by an adolescent indicates poor health in terms of functioning. Likewise, an individual’s genetic endowment is considered an influence because in most instances gene expression interacts with other factors before it causes disease or impairment in functioning.

The committee recognizes that children’s health is the result of a dynamic set of factors. In a few cases, randomized, controlled trials or experimental studies (or both) have demonstrated a causal link between a particular influence and health. In other cases, while there is evidence to suggest a link between the influence and health, a direct causal link has not been established. In determining whether to include a given influence in this report, the committee included factors that meet at least two of these three criteria: (1) the existence of randomized control trials or experimental studies that demonstrate a causal link; (2) longitudinal prospective studies plus other nonexperimental or quasi-experimental evidence that supports a link; and (3) observational studies, plausible theory, or animal studies that support a link. Furthermore, inclusion required a substantial body of evidence with replicated studies and multiple, independent laboratories or researchers reaching the same conclusions.

Typically, current research assesses the effect of a single or a small set of influences but does not allow an assessment of the relative importance of multiple influences in relation to one another. In the committee’s view, the relative lack of research on children’s health generally, and the interaction of various influences specifically, precludes a reliable ranking of influences. Instead, we have included all factors that meet a defined threshold of evidence and excluded those that, while plausible, do not yet have sufficient evidence to support their effect. The committee calls for research to allow refinement of the influences and their relative effect.

Data and Methods

Numerous federal, state, and local surveys and administrative data sources are used to inform policy and programmatic decisions. In specifying available data sources, the committee chose to focus on national data sources or state-level sources that are available in all or most states. Conducting a comprehensive review of the innumerable data sources that measure children’s health or a component of it in individual states or localities was not feasible. Instead, the committee highlights state or local examples to illustrate strategies proposed in the report.

Children Are Vital Assets of Society

Children have intrinsic value in their own right. In the committee’s view, fully protecting the health and growth of children is one of society’s primary responsibilities. Optimal health and development are necessary preconditions to provide the opportunity for all children to reach their inherent potential. The reality that some children do not have the opportunity to grow up healthy and become productive members of their communities and the nation has enormous ramifications for all. Failure to optimize the health and development of children will result in future burdens of dependence that come from an unhealthy and unskilled workforce and dysfunctional families. Furthermore, growing scientific evidence demonstrates that disparities in health have their origins in early childhood and, if not addressed, are compounded over the life course (Ben-Shlomo and Kuh, 2002; Hardy, Kuh, Langenberg, and Wadsworth, 2003; Halfon and Hochstein, 2002; Institute of Medicine, 2001b). Therefore, the committee undertook its task with the conviction that it is important for the whole of society to be committed to ensuring that children are as healthy as possible and that all children are afforded an opportunity to optimize their individual health and development. In the committee’s view, maximizing children’s health will provide immediate benefits to them as well as determine their capacity to contribute to society and the common good over the long term.

Critical Differences Between Children and Adults

Many other reports have examined issues related to the health of Americans generally. Thus, a legitimate question is: Why should a report focus specifically on the health of children? The answer is that there are many differences between children and adults. Therefore, it is inappropriate to assume that what enhances or impedes adult health translates directly into children’s health. While many factors may be relevant to both child and adult health, a wide range of factors affect them differentially.

Childhood Has a Long Reach

What happens to children early in their lives can have profound implications for later health and well-being during adulthood (Wadsworth, 1999). A great deal of information is emerging on the high degree to which early events and conditions of childhood serve as precursors of adult disease. From Neurons to Neighborhoods, a recent report of the National Academies, states: “What happens during the first months and years of life matters a lot, not because this period of development provides an indelible blueprint for adult well-being, but because it sets either a sturdy or fragile stage for what follows” (National Research Council and Institute of Medicine, 2000, p. 5). Experiences early in life establish a physical, psychological, and social foundation on which future development and adult health are based. This can include prenatal and perinatal insults as well as exposures in childhood that lead to negative adult health outcomes. For example, early exposure to ultraviolet light has implications for the development of melanoma in adulthood. Habits and behaviors developed during childhood can also lead to health problems in adulthood. Diet and exercise habits acquired in early childhood have been shown to have cumulative effects that alter adult health outcomes in the absence of appropriately targeted interventions.

Both positive and negative influences early in life not only have direct effects on health during childhood, but also act to influence future health at each stage of development. Both negative and positive factors and health disparities compound their effects over a lifetime. At each stage, previous health affects current and future health, and the cumulative effects of early differences in health may result in profound differences in later health (see Keating and Hertzman, 1999).

Failure to influence children’s health in a positive way may result in later excessive morbidity. The later consequences may be even more difficult and expensive to change than might prevention efforts put forth earlier in life. The capacity of an adult to contribute as a productive member of society may also be dramatically affected by poor health experienced as a child. This also means that there is often a long lag time between the measurable effects of interventions in childhood and changes in health later in life. This in turn makes it much more difficult to assess whether health is improving in both the short and the long run.

Community and Cultural Variation

Although there are some absolute notions of health (e.g., absence of disease), the manifestations of health differ across social and cultural groups. This is reflected in the differing notions of health across human societies and within societies over time. Common and technical use of terms like “disease,” “illness,” and “impairment” is embedded in a cultural context, which will determine whether certain symptoms, signs, or disease manifestations are considered normal or worthy of distinction in either a positive or negative way. For example, notions of normal body size differ substantially in different parts of the world and over generations. Aspects of health, social, and cultural norms influence concepts of health as well as understanding of the causes and consequence of the variety of its aspects. When these notions translate into individual and group behaviors and attitudes, they can have a major effect on health.

Culture also provides a framework for the use of home remedies. For example, in some Hispanic and Asian communities, health is a balance between “hot” and “cold,” and an imbalance in favor of one can cause illness necessitating a remedy from the other to restore harmony (Risser and Mazur, 1995). Other cultural variations that can be misconstrued are the traditional practices of cupping and coining, which can be mistaken for child abuse (Hansen, 1998), and home remedies for such folk illnesses as caída de mollera (fallen fontanelle), mal ojo (evil eye), and empacho (intestinal blockage).

In addition, social or cultural views on health, as well as the circumstances of a given community, may affect the priorities of that community in terms of what is considered important. It is therefore critical for specific societies and communities to define the measures they deem most salient to their local circumstances and for those working to improve health to take into account cultural differences and the priorities of that community. For example, a low-income community in which food is scarce and healthy children are defined by carrying extra weight may not consider obesity a priority health problem compared with reducing other more immediate threats to health, such as crime.

Use of Data to Improve Children’s Health

How can the nation assess whether movement toward the goal of optimizing children’s health society-wide is being achieved? Without the capacity to measure and monitor progress, there is no way to know whether changes in policy make a difference toward improving children’s health. Lack of valid and reliable information impedes comparisons across time or place or in response to interventions. Without data to measure and monitor children’s health, the effect of changes in the social, cultural, and physical environment will remain unknown.

What is measured is often what gets attention. Conversely, aspects that are more difficult to assess are more likely be ignored. This report addresses the questions of whether what is measured is what ought to be measured; whether it is being measured in an appropriate manner; and whether information is being used in a way that will optimize children’s health.