Introduction: Why Study Adolescence?
Adolescence has long been recognized as a period of heightened risk-taking and, accordingly, a stage that requires special oversight from adults.1 Nevertheless, expectations regarding this period—and views of how adolescents should be treated—have varied. A common subject of social commentary in the United States is that young people today begin adolescence too early and leave it too late.2 The decline in the age of onset of menarche for girls—from approximately age 17 in 1830 to just under age 13 by the middle of the twentieth century (Susman et al., 2010)—as well as the challenges of achieving financial independence in the current U.S. economy both support the idea of a protracted adolescence. This idea that adolescents undergo a protracted period of development is not unique to modern times, however. As early as 1563 an English statute decreed that all craftsmen should complete an apprenticeship of at least 7 years because “until a man grows into 23 years, he for the most part, though not always, is wild, without judgment and not of sufficient experience to govern himself” (Hibbert, 1987).
Most adolescents progress to adulthood with relatively little difficulty, experiencing excellent physical health and strength and not engaging in behaviors that put themselves or others at risk. Others, however, take many sorts of unhealthy risks—in their sexual behavior, in driving, in substance use, in criminal activity—or experience emotional distress or mental health disorders. For a substantial number of adolescents, the consequences are severe: they may limit a young person’s opportunities to grow into a productive adult, they are the source of lifelong health problems, and they result in a significant risk of injury and death for adolescents.3
Many adolescent risk behaviors—particularly poor driving, either with or without concomitant use of alcohol or illicit substances, and crime—also put others at risk, and all of these factors together make the prevention of risk behaviors in adolescence an important public health issue. Risky adolescent driving illustrates well the seriousness of the public health concern. According to the Centers for Disease Control and Prevention, one in three deaths among teenagers is caused by a motor vehicle crash, which translates into 4,544 deaths among 16- to 19-year-olds in 2005, in addition to the deaths of others involved in the crashes caused by adolescents. These statistics do not capture injuries or other damage, nor do they reflect the economic cost—the cost of all crashes involving drivers ages 15 to 20 in 2002 was $40.8 billion (U.S. Department of Transportation, 2003).
Researchers have produced a substantial body of work on the biological and psychological changes that occur during adolescence, as well as the family, peer, and cultural influences that shape adolescents’ lives in important ways. This evidence—as well as the evidence-based practice of health care practitioners and others who work with adolescents—can guide current and future efforts to promote healthy behavior and also to prevent risky behaviors that are prevalent during this stage of development. The Institute of Medicine and the National Research Council formed the Committee on the Science of Adolescence, with the support of the U.S. Department of Health and Human Services’ Administration for Children, Youth, and Families (ACF), the Office of the Assistant Secretary of Planning and Evaluation (ASPE), and the National Institute on Drug Abuse (NIDA). The committee planned and convened a series of three public workshops in 2008 and 2009 to review the science of adolescence from a
life-course perspective and to explore the implications of this research for the design, implementation, and evaluation of prevention programs for adolescents, as well as other means of fostering healthy development.
The three workshops examined scientific work on processes both within individuals and in the environment, including social factors that affect behavior during adolescence. The goals were to bridge multiple disciplines in the biological, health, social, and behavioral sciences; identify ways of integrating findings from each of these fields that can improve understanding of why adolescents engage in risky behavior; improve strategies for prevention and intervention; and flag areas in which further research is needed.
The workshop series began on November 20, 2008, with presentations by committee members (and one outside guest). The first workshop featured overviews on the physical and mental health status of adolescents and data trends on the nature, prevalence, historical trends, developmental course, and demographic variations of adolescent risk behaviors, including sexual risk-taking, substance use, criminal behavior, and risky driving. The afternoon presentations focused on individual processes that may inform prevention and intervention efforts. A panel on biological, cognitive, and psychosocial influences on adolescent risk behavior examined the extent to which context (e.g., family, peers, school, neighborhood) relates to or affects individual processes and how an understanding of individual development in adolescence may inform prevention and intervention. Areas of focus included puberty and neuroendocrine changes, brain development, cognition and decision making, and psychosocial development.
Following this workshop, the committee met and identified areas that would be the basis for the subsequent workshops. Following from the first workshop’s focus on individual-level influences, the committee planned the second workshop to focus on social and environmental influences. The committee also considered the importance of discussing integration among individual processes and social and environmental influences and therefore decided on a third workshop to focus on integrative thinking.
The second workshop—on social and environmental influences on adolescent risk behavior—was held on May 28, 2009. A series of presentations covered the following areas of influence: family, siblings, peers, schools, communities, and the media. Presenters explored evidence on the extent to which these various factors influence adolescent risk behavior and discussed how this knowledge can inform the development of prevention, health promotion, and treatment interventions.
Following the second workshop, the committee identified areas in which the integration of individual biological, cognitive, and psychosocial influences and social and environmental influences may further the understanding of adolescent risk behavior. Seven papers were commissioned around topics identified by the committee, and these papers served as the basis for the presentations at the third workshop, held on December 14, 2009. These presentations considered the impact of various influences and contexts—including public policy, biology, family, schools, and community—on adolescent risk behavior. Presenters considered overarching lessons about the genesis of risky behavior in adolescence, as well as how knowledge could be integrated across domains of influence. They discussed next steps in the science agenda and whether current approaches to the study of adolescent risk behavior should change and, if so, in what ways.
This report describes the information presented and discussed at the three workshops and highlights key observations from the evidence that is relevant to adolescent risk prevention and health promotion.4 We note that the workshop series included structured discussions designed to elicit varying research perspectives as well as more formal, data-based presentations—and that presenters took a variety of approaches to the tasks they were asked to undertake. This report, which is intended only to document what was presented and discussed during the three public workshops, reflects this variation.
Experiences in the prenatal and early childhood periods may have significant influences on life-course development, including adolescence, predisposing individuals to particular outcomes. Nevertheless, rather than life-course developmental issues, the workshop series focused on adolescent risk behaviors for several reasons. First, this developmental period presents significant threats to young people’s health, development, and safety. Second, research on this topic is fragmented across disciplines: although many biological processes and other influences that are specific to this period increase susceptibility to risk-taking and therefore have a lifelong influence on health and well-being, research on them has remained overly segregated within individual disciplines. Bringing this work together is therefore needed to advance research and its applications. For example, recent research on adolescent brain development has provided new insights and opened up new possibilities for intervention. This research, discussed in detail in Chapter 3, suggests that there may be some neurobiological factors or mechanisms that affect adolescents regardless of their social context. This is not to say that social and cultural
factors are unimportant. The experience of adolescence—and patterns of risk-taking—are likely to vary in important ways around the world. However, very little research has been conducted on cross-national variation in adolescent risk behavior; consequently, this report reflects the fact that the bulk of the research currently available draws on data collected in the United States.
STRUCTURE OF THE REPORT
Following this introduction, Chapter 2 sets the stage for an exploration of the research by providing a portrait of the physical and mental health status of adolescents in the United States and describes the risks some young people are taking. The next three chapters describe theoretical explanations for why adolescence is a high-risk stage of development and why some adolescents engage in more risky behaviors than others. Chapter 3 examines biobehavioral processes related to risk-taking, and Chapter 4 focuses on social and cognitive theories regarding decision making. Chapter 5 describes research on sociological and contextual factors and some of the variables that may help link context and behavior, such as values, social skills, and social supports. The closing chapter explores possibilities for integrating these perspectives, highlighting practical approaches to minimizing risk. It also describes specific areas in which additional research is needed.