APPENDIX D

Distribution of Risk and Protective Factors and Substance Use, by Age and Gender

Substance Use, by Age and Gender

In looking at any set of risk and protective factors relative to adolescent substance use, it is important to begin with an understanding of the ways in which substance use and other activities and relationships change with age. As mentioned in Chapter 2, behavior, especially substance-using behavior, can change rapidly during adolescence, and it can be potentially misleading to treat 12 to 17 year olds as an undifferentiated age group without closer inspection. The adolescent sample represented in the 1997 NHSDA can be thought of as six consecutive 1-year age groups.¹ Figure D.1 shows the association between age and substance use, separately for males and females, for four kinds of substances-cigarettes, alcohol, marijuana, and any illicit drug other than marijuana² -showing two distinct measures for each substance, namely, whether it was ever used in an individual's lifetime and in the past year. These calendrical categories are not exclusive: A person who used in the past year is included in the ever-used group.

Based on 1997 NHSDA data, we estimated that less than 15 percent of male and female 12 year olds in 1997 had ever smoked a cigarette. But for those aged 17, this figure was about 60 percent, with a slightly higher percentage among males than females. Although not shown, the percentage who smoked within the past month, though much lower at every age, showed a very similar pattern, rising from about 6 percent at age 12 to about 39 percent at age 17, with only slight differences between males and females. The same pattern of steady increase with age and minimal differences between males and females was characteristic of alcohol use, marijuana use, and the use of any illicit drug other than marijuana. Alcohol was used by the highest percentage of adolescents, closely trailed by cigarettes (with a somewhat flatter age distribution). Approximately half as many adolescents used marijuana in the past year as used alcohol or cigarettes. This was true at every year of age from 12 to 17 years. In addition, somewhat more used marijuana at every age than used all other illicit drugs. For example, among 17 year olds, 56 percent used alcohol, 39 percent smoked cigarettes, 28 percent used marijuana, and 15 percent used any illicit drug other than marijuana.

This pattern of steadily increasing drug use at each age, with relatively small if any differences between males and females, was common to white, black, and Hispanic youths. White youths reported higher rates of cigarette smoking than black or Hispanic youths, and black adolescents reported generally lower prevalence of alcohol and of illicit drugs other than marijuana. However, prevalence of marijuana use did not vary by race or ethnicity.

Figure D.1 Prevalence of Lifetime and Past Year Substance Use in the U.S. Civilian, Noninstitutionalized Population Aged 12 to 17, by Age and Gender

Source: Office of Applied Studies, SAMHSA, 1997 National Household Survey on Drug Abuse.

Risk and Protective Factors: Variation by Age

Figure D.2 displays the prevalence by age group of a series of activities typically engaged in by adolescents, and thought to comprise protective factors inhibiting substance use, including team sports, volunteer activities, school-related clubs, Scouting, private lessons (music, dance, athletics), school musical participation (band, orchestra, or choir), church choir, and student government. The most common activity was team sports, which more than half of all adolescents participated in, excepting 17 year olds (46 percent). The least prevalent major activity was 4-H (about 5 percent of youths) and scouting (about 8 percent for older teens); clearly, participation in scouting peaked in middle childhood and then declined in early adolescence.

Source: Office of Applied Studies, SAMHSA, 1997 National Household Survey on Drug Abuse.

There were changes in the composition of activities with age. Scouting, private lessons, school musical groups, and team sports participation diminished, while student government, school clubs, and volunteer activities increased. Aside from the composition of activities, there were modest changes in the total number of activities reported by members of different age groups. The 12-year-old group included a few percentage points more adolescents with none or with a large number of activities than the older age groups.

Figure D.3 displays data on other categories of past year behavior or attitudes that have been identified as risk or protective factors. Quite consistent was the rise in the percentage of adolescents whoreported having at least a few close friends who binged on alcohol one to two times a week, smoked one or more packs of cigarettes per day, tried or used marijuana, or tried or used heroin or used cocaine monthly, all of which paralleled the association of older age with greater likelihood of self-use of drugs. More adolescents reported having a few close friends who tried or used marijuana or who smoked at least a pack of cigarettes per day than friends who binged one to two times a week on alcohol (among 17 year olds, e.g., marijuana, 76 percent, and cigarettes, 73 percent, vs. alcohol, 66 percent).

Source: Office of Applied Studies, SAMHSA, 1997 National Household Survey on Drug Abuse.

There was a similar steady increase with age in the percentage who said particular drugs were fairly easy or very easy to get or that anyone had ever offered them or tried to sell them marijuana or, less frequently, cocaine (these data are not displayed in the figure). For example, 2 percent of 12 year olds but nearly 20 percent of 17 year olds said they had been offered cocaine, and the percentage who considered marijuana fairly or very easy to get rose from one quarter of 12 year olds to more than three quarters of 17 year olds. There was no difference between males and females with respect to the availability of marijuana, but females between 14 and 16 (although not older or younger) were more likely than males of the same ages, by 5 to 14 percentage points, to say that cocaine, crack, LSD, or heroin were easy to get. Perhaps this reflects the more rapid (physical and social) maturation of girls in these midteen years.

Religious beliefs, which were "very important" to more than 84 percent of adolescents, were considered a protective factor, along with attendance at religious services, which more than 80 percent of youths had reported in the previous year, and more than 40 percent attended religious services at least once per week. There was little change in the importance of religious beliefs with age; the importance and influence of religious beliefs declined slightly among the older groups. Conversely, delinquent activity was considered a risk factor, and about 17 percent of 12 to 17 year olds shoplifted (see Figure D.3) and about 8percent engaged in gang fighting over the previous year. In both cases, there was a modest increase from the 12-year-old to the 14-year-old age group, but then the prevalence of these delinquent activities fell slightly from age 14 to age 17.

Figure D.4 refers to patterns of communication between adolescents, their parents, and others. There was a general tendency for communication with parents, a presumptive protective factor, to be lower among older age groups. The percentage of adolescents who could talk to one or the other parent about a serious problem declined from about 88 percent of 12 year olds to 74 percent of 17 year olds. However, the percentage who considered a parent the most likely person they would talk to about a serious problem dropped much more sharply, from 68 percent of 12 year olds to 41 percent of 17 year olds. Parents of older adolescents were also more likely to be considered more lenient on homework, dress, or curfew. For example, 19 percent of parents of 12 year olds but 32 percent of parents of 17 year olds were reported to be "not at all strict" about homework. The percentage of youths reporting arguments at least several times per week with parents dropped very slightly from about 26 percent among younger adolescents to 23 percent among older ones. Communication about drugs or alcohol with parents or older adults did not vary appreciably or in any particular trend, with about 55 percent of youths reporting such communication in the past year.

Source: Office of Applied Studies, SAMHSA, 1997 National Household Survey on Drug Abuse.

¹ Because the survey data were collected continuously throughout the year and age is determined as age at the time of interview, individuals who were 12 years old at the time of the survey can be separated in birth date by as much as 2 years-that is, an individual born in late January 1984 could be interviewed at 12 years of age in early January 1997; and an individual born nearly 2 years later in mid-December 1985 could be interviewed at 12 years old in late December 1997. The age groups are therefore not clean successive birth cohorts. In addition, although there are differences in substance use by birth cohort, these differences are, for the measures used in this discussion, overshadowed by the degree of change associated with age alone.

² Illicit drugs other than marijuana include cocaine, heroin, hallucinogens such as LSD and PCP, inhalants such as glue and ether and nonmedical use of prescription-type psychotherapeutic drugs such as sedatives, stimulants, and pain-killers. Alcohol and tobacco products are referred to as licit drugs because they can be legally sold to and used for nonmedical purposes by adults; this should not be taken to mean that the law condones the sale of these drugs to (or their use by) adolescents.

This page was last updated on June 01, 2008.

SAMHSA, an agency in the Department of Health and Human Services, is the Federal Government's lead agency for improving the quality and availability of substance abuse prevention, addiction treatment, and mental health services in the United States.