Youth Risk Behavior Surveillance --- United States, 2001

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Jo Anne Grunbaum, Ed.D.¹Laura Kann, Ph.D.¹Steven A. Kinchen¹Barbara Williams, Ph.D.²James G. Ross, M.S.³Richard Lowry, M.D., M.S.¹Lloyd Kolbe, Ph.D.^{1

1}Division of Adolescent and School Health
National Center for Chronic Disease Prevention and Health Promotion²Westat, Rockville, Maryland³ORC Macro, Calverton, Maryland

Problem/Condition: Priority health-risk behaviors, which contribute to the leading causes of mortality and morbidity among youth and adults, often are established during youth, extend into adulthood, are interrelated, and are preventable.

Reporting Period Covered: This report covers data during February--December 2001.

Description of System: The Youth Risk Behavior Surveillance System (YRBSS) monitors six categories of priority health-risk behaviors among youth and young adults; these behaviors contribute to unintentional injuries and violence; tobacco use; alcohol and other drug use; sexual behaviors that contribute to unintended pregnancy and sexually transmitted diseases (STDs), including human immunodeficiency virus (HIV) infection; unhealthy dietary behaviors; and physical inactivity. The YRBSS includes a national school-based survey conducted by CDC as well as state, territorial, and local school-based surveys conducted by education and health agencies. This report summarizes results from the national survey, 34 state surveys, and 18 local surveys conducted among students in grades 9--12 during February--December 2001.

Results: In the United States, approximately three fourths of all deaths among persons aged 10--24 years result from only four causes: motor-vehicle crashes, other unintentional injuries, homicide, and suicide. Results from the 2001 national Youth Risk Behavior Survey demonstrated that numerous high school students engage in behaviors that increase their likelihood of death from these four causes: 14.1% had rarely or never worn a seat belt during the 30 days preceding the survey; 30.7% had ridden with a driver who had been drinking alcohol; 17.4% had carried a weapon during the 30 days preceding the survey; 47.1% had drunk alcohol during the 30 days preceding the survey; 23.9% had used marijuana during the 30 days preceding the survey; and 8.8% had attempted suicide during the 12 months preceding the survey. Substantial morbidity and social problems among young persons also result from unintended pregnancies and STDs, including HIV infection. In 2001, 45.6% of high school students had ever had sexual intercourse; 42.1% of sexually active students had not used a condom at last sexual intercourse; and 2.3% had ever injected an illegal drug. Two thirds of all deaths among persons aged >25 years result from only two causes: cardiovascular disease and cancer. The majority of risk behaviors associated with these two causes of death are initiated during adolescence. In 2001, 28.5% of high school students had smoked cigarettes during the 30 days preceding the survey; 78.6% had not eaten >5 servings per day of fruits and vegetables during the 7 days preceding the survey; 10.5% were overweight; and 67.8% did not attend physical education class daily.

Public Health Actions: Health and education officials at national, state, and local levels are using these YRBSS data to analyze and improve policies and programs to reduce priority health-risk behaviors among youth. The YRBSS data also are being used to measure progress toward achieving 16 national health objectives for 2010 and 3 of the 10 leading health indicators.

Introduction

In the United States, 70.6% of all deaths among youth and young adults aged 10--24 years result from only four causes: motor-vehicle crashes (31.4%), other unintentional injuries (12%), homicide (15.3%), and suicide (11.9%) (1). Substantial morbidity and social problems also result from the approximately 870,000 pregnancies that occur each year among women aged 15--19 years (2) and the estimated 3 million cases of sexually transmitted diseases (STDs) that occur each year among persons aged 10--19 years (3).

Among adults aged >25 years, 64.6% of all deaths in the United States result from cardiovascular disease (41%) and cancer (23.6%) (1). Leading causes of mortality and morbidity among all age groups in the United States are related to the following categories of health behavior: behaviors that contribute to unintentional injuries and violence; tobacco use; alcohol and other drug use; sexual behaviors that contribute to unintended pregnancy and STDs, including human immunodeficiency virus (HIV) infection; unhealthy dietary behaviors; and physical inactivity. These behaviors are frequently interrelated and often are established during youth and extend into adulthood.

To monitor priority health-risk behaviors in each of these categories among youth and young adults, CDC developed the Youth Risk Behavior Surveillance System (YRBSS) (4). The YRBSS includes national, state, territorial, and local school-based surveys of students in grades 9--12. National surveys were conducted in 1991, 1993, 1995, 1997, 1999, and 2001. Comparable state and local surveys also were conducted (Box).

This report summarizes results from the 2001 national school-based survey and trends during 1991--2001 in selected risk behaviors. Data from 34 state and 18 local school--based surveys also are included. The national survey and all of the state and local surveys except one were conducted during spring 2001. Hawaii conducted their survey during fall 2001.

Methods

Sampling

National Youth Risk Behavior Survey

The 2001 national school-based YRBS employed a three-stage cluster sample design to produce a nationally representative sample of students in grades 9--12. The first stage sampling frame contained 1,256 primary sampling units (PSUs), consisting of large counties or groups of smaller, adjacent counties. From the 1,256 PSUs, 57 were selected from 16 strata formed on the basis of the degree of urbanization and the percentage of black* and Hispanic^† students in the PSU. PSUs were selected with probability proportional to school enrollment size. At the second sampling stage, 199 schools were selected with probability proportional to school enrollment size. To enable separate analysis of data for black and Hispanic students, schools with substantial numbers of black and Hispanic students were sampled at higher rates than all other schools. The third stage of sampling consisted of randomly selecting one or two intact classes of a required subject (e.g., English or social studies) from grades 9--12 at each chosen school. All students in selected classes were eligible to participate in the survey.

A weighting factor was applied to each student record to adjust for nonresponse and for varying probabilities of selection, including those resulting from oversampling of black and Hispanic students. Numbers of students in other racial/ethnic populations (excluding white^§, black, and Hispanic students) were too low for meaningful analysis in this report. Weights were scaled so that 1) the weighted count of students was equal to the total sample size, and 2) the weighted proportions of students in each grade matched national population proportions.

National data are representative of students in grades 9--12 in public and private schools in the 50 states and the District of Columbia. SUDAAN was used to compute 95% confidence intervals, which were used to determine differences between subpopulations at the p<0.05 level (5). Differences between prevalence estimates were considered statistically significant if the 95% confidence intervals did not overlap. Secular trends were analyzed by using logistic regression analyses that controlled for sex, grade, and race/ethnicity and that simultaneously assessed linear and higher order (i.e., quadratic) time effects (6). Quadratic trends indicate a significant but nonlinear trend in the data. When the trend includes significant linear and quadratic components, the data demonstrate certain nonlinear variation (e.g., leveling off or change of direction) in addition to a linear trend. For the national YRBS, 13,627 questionnaires were completed in 150 schools. Of the 13,627 completed questionnaires, 26 failed quality control^¶ and were excluded from analyses for a total of 13,601 usable questionnaires. The school response rate was 75%, and the student response rate was 83%, resulting in an overall response rate of 63% (Table 1). Additional information regarding the YRBS is available at http://www.cdc.gov/yrbs.

In 2001, each state and local school-based YRBS employed a two-stage cluster sample design to produce representative samples of students in grades 9--12 in their jurisdiction. In the majority of states and cities, schools were selected with probability proportional to school enrollment size. At the second sampling stage, intact classes of a required subject or intact classes during a required period (e.g., second period) were selected randomly. All students in selected classes were eligible to participate in the survey. Certain states and cities modified these procedures to meet their individual needs. For example, all schools, rather than a sample of schools were selected to participate.

In 2001, the student sample sizes for the state and local YRBS ranged from 955 to 7,191. School response rates ranged from 42% to 100%; student response rates ranged from 48% to 96%; and overall response rates ranged from 41% to 90% (Table 1). School response rate multiplied by student response rate produces an overall response rate for each site. For surveys from 22 states and 14 large cities, each with an overall response rate of >60% and appropriate documentation, the data were weighted and are considered representative of students in grades 9--12 in that jurisdiction. For surveys from 12 states and 4 large cities that did not have an overall response rate of >60% and appropriate documentation, the data were not weighted. Unweighted data from these 12 states and 4 large cities apply only to students participating in the survey. The Illinois survey excludes students from Chicago; the Louisiana survey excludes students from New Orleans; and the New York survey excludes students from New York City.

Body mass index (BMI) was calculated from self-reported height and weight and then applied to reference data from the National Health and Nutrition Examination Survey (7) to determine the percentage of students who were at risk for becoming overweight and who were overweight. At risk for becoming overweight was defined as a BMI >85th percentile and <95th percentile by age and sex. Overweight was defined as a BMI >95th percentile by age and sex. A BMI >95th percentile by age and sex among youth is approximately equivalent to a BMI >30 among adults. For an adult, a BMI of 30 is approximately 30 pounds overweight.

Data Collection

Survey procedures for the national, state, and local surveys were designed to protect students' privacy by allowing for anonymous and voluntary participation. Students completed the self-administered questionnaire during one class period and recorded their responses directly on a computer-scannable booklet or answer sheet. The core questionnaire contained 87 multiple-choice questions. To meet individual needs, some states and large cities added or deleted some questions. Before the survey was administered, local parental permission procedures were followed.

Results

Behaviors That Contribute to Unintentional Injuries

Seat Belt Use

Nationwide, 14.1% of students had rarely or never worn seat belts when riding in a car driven by someone else (Figure 1) (Table 2). Male students (18.1%) were significantly more likely than female students (10.2%) to have rarely or never worn seat belts. This significant sex difference was identified for white and Hispanic students and for students in all of the grade subpopulations. Prevalence of rarely or never wearing seat belts varied fourfold from 7.5% to 27.4% (median: 14.9%) across state surveys, and varied sixfold from 6.7% to 38.2% (median: 13.5%) across local surveys (Table 3).

Nationwide, 25.3% of students had ridden a motorcycle during the 12 months preceding the survey. Of these students, 37.2% rarely or never wore a motorcycle helmet (Table 2). Male students (40.9%) were significantly more likely than female students (30.1%) to have rarely or never worn a motorcycle helmet. This significant sex difference was identified for white students and students in grade 12. Overall, Hispanic students (55.3%) were significantly more likely than white students (33.6%) to report this behavior. This significant racial/ethnic difference was identified for both female and male students. Prevalence of rarely or never wearing a motorcycle helmet varied threefold from 19.5% to 66.1% (median: 40.3%) across state surveys and from 30.6% to 67.6% (median: 42.5%) across local surveys (Table 3).

Nationwide, 65.1% of students had ridden a bicycle during the 12 months preceding the survey. Of these students, 84.7% rarely or never wore a bicycle helmet (Table 2). Overall, black students (90.7%) were significantly more likely than white students (83.6%) to have rarely or never worn a bicycle helmet. This significant racial/ethnic difference was identified for female students. Prevalence of rarely or never wearing a bicycle helmet ranged from 54.8% to 95.8% (median: 88.6%) across state surveys and from 70.1% to 94.4% (median: 87.9%) across local surveys (Table 3).

During the 30 days preceding the survey, 30.7% of students nationwide had ridden >1 times with a driver who had been drinking alcohol (Figure 2) (Table 4). Male students in grade 11 (32.8%) were significantly more likely than female students in grade 11 (25.4%) to report this behavior. Overall, Hispanic students (38.3%) were significantly more likely than white and black students (30.3% and 27.6%, respectively) to have ridden with a driver who had been drinking alcohol. This significant racial/ethnic difference was identified for female students. Prevalence of riding with a driver who had been drinking alcohol ranged from 17.1% to 43.5% (median: 31.8%) across state surveys and from 19.3% to 39.6% (median: 29.5%) across local surveys (Table 5).

During the 30 days preceding the survey, 13.3% of students nationwide had driven a car or other vehicle >1 times after drinking alcohol (Table 4). Male students (17.2%) were significantly more likely than female students (9.5%) to have driven after drinking alcohol. This significant sex difference was identified for all the racial/ethnic subpopulations and for students in grades 9, 11, and 12. Overall, white students and Hispanic students (14.7% and 13%, respectively) were significantly more likely than black students (7.7%) to have driven after drinking alcohol. White and Hispanic female students (10.9% and 10.5%, respectively) were significantly more likely than black female students (3.3%), and white male students (18.6%) were significantly more likely than black male students (12.5%) to report this behavior. Overall, students in grade 10 (10.4%) were significantly more likely than students in grade 9 (6.6%) to have driven after drinking alcohol; students in grade 11 (16.7%) were significantly more likely than students in grades 9 and 10 (6.6% and 10.4%, respectively) to report this behavior; and students in grade 12 (22.1%) were significantly more likely than students in grades 9, 10, and 11 (6.6%, 10.4%, and 16.7%, respectively) to report this behavior. Prevalence of driving after drinking alcohol varied fourfold from 6.4% to 26.8% (median: 13%) across state surveys and varied fourfold across local surveys from 3.8% to 13.8% (median: 8%) (Table 5).

Behaviors That Contribute to Violence

Nationwide, 17.4% of students had carried a weapon (e.g., a gun, knife, or club) on >1 of the 30 days preceding the survey (Table 6). Male students (29.3%) were significantly more likely than female students (6.2%) to have carried a weapon. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Black female students (8.6%) were significantly more likely than white female students (5.1%) to have carried a weapon, and white male students (31.3%) were significantly more likely than black male students (22.4%) to have done so. Prevalence of carrying a weapon ranged from 10.6% to 22.9% (median: 16.2%) across state surveys and from 8.3% to 21.2% (median: 13.7%) across local surveys (Table 7).

Nationwide, 5.7% of students had carried a gun on >1 of the 30 days preceding the survey (Table 6). Male students (10.3%) were significantly more likely than female students (1.3%) to have carried a gun. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Prevalence of carrying a gun varied threefold from 2.9% to 10.1% (median: 5%), across state surveys and varied fivefold from 1.3% to 7.1% (median: 4.8%), across local surveys (Table 7).

Among students nationwide, 33.2% had been in a physical fight >1 times during the 12 months preceding the survey (Table 8). Male students (43.1%) were significantly more likely than female students (23.9%) to have been in a physical fight. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Black and Hispanic female students (29.6% and 29.3%, respectively) were significantly more likely than white female students (21.7%) to report this behavior. Overall, students in grades 9 and 10 (39.5% and 34.7%, respectively) were significantly more likely than students in grades 11 and 12 (29.1% and 26.5%, respectively) to report this behavior. Across state surveys, prevalence of being in a physical fight ranged from 25.9% to 35.6% (median: 31.4%) (Table 9). Across local surveys, prevalence ranged from 30.3% to 43.4% (median: 34.6%).

Nationwide, 4% of students had been treated by a doctor or nurse for injuries sustained in a physical fight >1 times during the 12 months preceding the survey (Table 8). Male students (5.2%) were significantly more likely than female students (2.9%) to have been injured in a physical fight. This significant sex difference was identified for white students and students in grades 9 and 12. Overall, black students (5.3%) were significantly more likely than white students (3.4%) to have been injured in a physical fight. This significant racial/ethnic difference was identified for female students. Across state surveys, prevalence of injurious physical fighting varied threefold from 2% to 6.4% (median: 3.5%) (Table 9). Across local surveys, prevalence ranged from 3.9% to 7.1% (median: 4.6%).

Nationwide, 9.5% of students had been hit, slapped, or physically hurt on purpose by their boyfriend or girlfriend >1 times during the 12 months preceding the survey (Table 8). Prevalence of dating violence ranged from 6.9% to 18.1% (median: 10.3%) across state surveys and from 6% to 17.2% (median: 10.2%) across local surveys (Table 9).

Nationwide, 7.7% of students had ever been forced to have sexual intercourse when they did not want to (Table 8). Female students (10.3%) were significantly more likely than male students (5.1%) to have been forced to have sexual intercourse. This significant sex difference was identified for white and Hispanic students and students in grades 10, 11, and 12. Overall, black students (9.6%) were significantly more likely than white students (6.9%) to have been forced to have sexual intercourse. This significant racial/ethnic difference was identified for male students. Prevalence of forced sexual intercourse ranged from 5.4% to 12.1% (median: 8.5%) across state surveys and from 5.6% to 13.3% (median: 9.2%) across local surveys (Table 9).

Nationwide, 6.6% of students had missed >1 days of school during the 30 days preceding the survey because they felt unsafe at school or on their way to or from school (Table 10). Overall, Hispanic and black students (10.2% and 9.8%, respectively) were significantly more likely than white students (5%) to have missed school because they felt unsafe. This significant racial/ethnic difference was identified for both male and female students. Overall, students in grade 9 (8.8%) were significantly more likely than students in grades 11 and 12 (5.9% and 4.4%, respectively) to report this behavior. Prevalence across state surveys varied sixfold from 3% to 16.9% (median: 7.3%) (Table 11). Prevalence across local surveys ranged from 6.6% to 17% (median: 11.4%).

Among students nationwide, 6.4% carried a weapon on school property on >1 of the 30 days preceding the survey (Table 10). Male students (10.2%) were significantly more likely than female students (2.9%) to have carried a weapon on school property. This significant sex difference was identified for white and Hispanic students and students in all the grade subpopulations. Prevalence of carrying a weapon on school property varied fourfold from 2.4% to 10.3% (median: 6.2%) across state surveys and ranged from 4.1% to 9.3% (median: 5.5%) across local surveys (Table 11).

Nationwide, 8.9% of students had been threatened or injured with a weapon on school property >1 times during the 12 months preceding the survey (Table 10). Male students (11.5%) were significantly more likely than female students (6.5%) to have been threatened or injured with a weapon on school property. This significant sex difference was identified for white and black students and students in all the grade subpopulations. Overall, students in grade 9 (12.7%) were significantly more likely than students in grades 10, 11, and 12 (9.1%, 6.9%, and 5.3%, respectively) to have been threatened or injured with a weapon on school property, and students in grade 10 (9.1%) were significantly more likely than students in grade 12 (5.3%) to report this behavior. Prevalence of being threatened or injured with a weapon on school property ranged from 5.9% to 11.2% (median: 8.5%) across state surveys and from 7.9% to 14.8% (median: 9.8%) across local surveys (Table 11).

Nationwide, 12.5% of students had been in a physical fight on school property >1 times during the 12 months preceding the survey (Table 10). Male students (18%) were significantly more likely than female students (7.2%) to have been in a physical fight on school property. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Overall, black students (16.8%) were significantly more likely than white students (11.2%) to have been in a physical fight on school property. Black and Hispanic female students (12.7% and 11%, respectively) were significantly more likely than white female students (5.4%) to report this behavior. Overall, students in grades 9 and 10 (17.3% and 13.5%, respectively) were significantly more likely than students in grades 11 and 12 (9.4% and 7.5%, respectively) to have been in a physical fight on school property, and students in grade 9 (17.3%) were significantly more likely than students in grade 10 (13.5%) to report this behavior. Across state surveys, prevalence of having engaged in a physical fight on school property ranged from 8.8% to 14.2% (median: 11.8%) (Table 11). Across local surveys, prevalence ranged from 11.2% to 21.5% (median: 14%).

Nationwide, during the 12 months preceding the survey, 28.3% of students had felt so sad or hopeless almost every day for >2 weeks in a row that they stopped doing some usual activities (Table 12). Overall, female students (34.5%) were significantly more likely than male students (21.6%) to have felt sad or hopeless almost every day for >2 weeks. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Overall, Hispanic students (34%) were significantly more likely than black and white students (28.8% and 26.5%, respectively) to have felt sad or hopeless almost every day for >2 weeks. Hispanic female students (42.3%) were significantly more likely than white female students (32.3%) and Hispanic male students (25.4%) were significantly more likely than white male students (20.5%) to report this behavior. Prevalence of feeling sad or hopeless ranged from 20.5% to 30.7% (median: 27.2%) across state surveys and from 24.2% to 35.3% (median: 31.1%) across local surveys (Table 13).

During the 12 months preceding the survey, 19% of students had seriously considered attempting suicide (Table 12). Female students (23.6%) were significantly more likely than male students (14.2%) to have considered attempting suicide. This significant sex difference was identified for all the racial/ethnic subpopulations and students in grades 9, 10, and 11. Overall, white and Hispanic students (19.7% and 19.4%, respectively) were significantly more likely than black students (13.3%) to have considered attempting suicide. Hispanic and white female students (26.5% and 24.2%, respectively) were significantly more likely than black female students (17.2%), and white male students (14.9%) were significantly more likely than black male students (9.2%) to have considered attempting suicide. Prevalence of seriously considering suicide ranged from 14.6% to 21.9% (median: 18.4%) across state surveys and from 10% to 21% (median: 16%) across local surveys (Table 13).

During the 12 months preceding the survey, 14.8% of students nationwide had made a specific plan to attempt suicide (Table 12). Overall, female students (17.7%) were significantly more likely than male students (11.8%) to have made a suicide plan. This significant sex difference was identified for all the racial/ethnic subpopulations and students in grades 9, 10, and 11. Overall, white and Hispanic students (15.3% and 14.1%, respectively) were significantly more likely than black students (10.3%) to have made a suicide plan. White female students (18%) were significantly more likely than black female students (13%), and white male students (12.5%) were significantly more likely than black male students (7.5%) to have made a suicide plan. Overall, students in grade 9 (16%) were significantly more likely than students in grade 12 (12.2%) to have made a suicide plan. Prevalence of having made a suicide plan ranged from 11.3% to 17.7% (median: 13.9%) across state surveys and from 7.9% to 16.9% (median: 13.3%) across local surveys (Table 13).

Nationwide, 8.8% of students had attempted suicide >1 times during the 12 months preceding the survey (Figure 3) (Table 12). Female students (11.2%) were significantly more likely than male students (6.2%) to have attempted suicide. This significant sex difference was identified for white and Hispanic students and students in grades 9, 10, and 11. Overall, Hispanic students (12.1%) were significantly more likely than black and white students (8.8% and 7.9%, respectively) to have attempted suicide. This significant racial/ethnic difference was identified for Hispanic female students. Overall, students in grades 9, 10, and 11 (11%, 9.5%, and 8.3%, respectively) were significantly more likely than students in grade 12 (5.5%) to have attempted suicide. The percentage of students attempting suicide ranged from 6.3% to 13.4% (median: 8.6%) across state surveys and from 7.4% to 13% (median: 10.4%) across local surveys (Table 13). Nationwide, 2.6% of students made a suicide attempt during the 12 months preceding the survey that resulted in an injury, poisoning, or overdose that had to be treated by a doctor or nurse (Table 12). Overall, students in grades 9 and 10 (3.2% and 3%, respectively) were significantly more likely than students in grade 12 (1.6%) to have made a suicide attempt that required medical attention. Prevalence of injurious suicide attempts varied fourfold from 1.2% to 4.6% (median: 2.5%) across state surveys and varied threefold from 1.7% to 5.7% (median: 3.4%) across local surveys (Table 13).

Tobacco Use

Nationwide, 63.9% of students had ever tried cigarette smoking (even one or two puffs) (i.e., lifetime cigarette use) (Table 14). Male students (66.3%) were significantly more likely than female students (61.6%) to have ever tried cigarette smoking. Overall, Hispanic students (69.3%) were significantly more likely than black students (58.3%) to have ever tried cigarette smoking. Hispanic female students (67.8%) were significantly more likely than black female students (56.7%), and Hispanic and white male students (70.9% and 67.4%, respectively) were significantly more likely than black male students (59.9%) to report this behavior. Overall, students in grades 11 and 12 (65.9% and 71.1%, respectively) were significantly more likely than students in grade 9 (58.4%) to have ever tried cigarette smoking, and students in grade 12 (71.1%) were significantly more likely than students in grade 10 (62.6%) to report this behavior. Prevalence of lifetime cigarette use ranged from 30.5% to 71.6% (median: 66%) across state surveys and from 48.9% to 68% (median: 58%) across local surveys (Table 15).

One fifth of students (20%) nationwide had ever smoked >1 cigarettes every day for 30 days (i.e., lifetime daily cigarette use) (Table 14). Overall, white students (23.9%) were significantly more likely than Hispanic and black students (12.4% and 7.7%, respectively), and Hispanic students (12.4%) were significantly more likely than black students (7.7%) to report lifetime daily cigarette use. These significant racial/ethnic differences were identified for female students. White male students (24.7%) were significantly more likely than Hispanic and black male students (13.4% and 9%, respectively) to report lifetime daily cigarette use. Overall, students in grades 11 and 12 (22.1% and 26.9%, respectively) were significantly more likely than students in grade 9 (14.3%) to report lifetime daily cigarette use, and students in grade 12 (26.9%) were significantly more likely than students in grade 10 (19.1%) to report this behavior. Across state surveys, prevalence of lifetime daily cigarette use varied threefold from 8.5% to 25.6% (median: 19.5%) (Table 15). Across local surveys, prevalence varied threefold from 5.7% to 16.8% (median: 9.4%).

Nationwide, 28.5% of students had smoked cigarettes on >1 of the 30 days preceding the survey (i.e., current cigarette use) (Figure 4) (Table 14). White and Hispanic students (31.9% and 26.6%, respectively) were significantly more likely than black students (14.7%) to report current cigarette use. This significant racial/ethnic difference was identified for both female and male students. Overall, students in grade 12 (35.2%) were significantly more likely than students in grades 9 and 10 (23.9% and 26.9%, respectively) to report current cigarette use. Across state surveys, prevalence of current cigarette use varied fourfold from 8.3% to 35.3% (median: 27.6%) (Table 15). Across local surveys, prevalence ranged from 11.9% to 24.7% (median: 17%).

Nationwide, 13.8% of students had smoked cigarettes on >20 of the 30 days preceding the survey (i.e., current frequent cigarette use) (Table 14). Overall, white students (17.2%) were significantly more likely than Hispanic and black students (7.3% and 4.6%, respectively) to report current frequent cigarette use. This significant racial/ethnic difference was identified for both female and male students. Overall, students in grades 11 and 12 (15.2% and 21%, respectively) were significantly more likely than students in grade 9 (8.9%) to report current frequent cigarette use, and students in grade 12 (21%) were significantly more likely than students in grade 10 (12.3%) to report this behavior. Prevalence of current frequent cigarette use varied fourfold from 4.2% to 18.8% (median: 14%) across state surveys and varied fourfold from 2.7% to 9.9% (median: 4.8%) across local surveys (Table 15).

Nationwide, 4.1% of students who reported current cigarette use, smoked >10 cigarettes per day on the days they smoked (Table 14). Overall, male students (5.2%) were significantly more likely than female students (3.1%) to smoke >10 cigarettes per day. This significant sex difference was identified for white students. Overall, white students (5.3%) were significantly more likely than Hispanic and black students (1.8% and 1.1%, respectively) to smoke >10 cigarettes per day. This significant racial/ethnic difference was identified for male students. White female students (4%) were significantly more likely than black female students (0.7%) to smoke >10 cigarettes per day. Overall, students in grades 11 and 12 (4.8% and 6.6%, respectively) were significantly more likely than students in grade 9 (2.2%) to smoke >10 cigarettes per day, and students in grade 12 (6.6%) were significantly more likely than students in grade 10 (3.6%) to report this behavior. Prevalence varied sevenfold from 1% to 7.3% (median: 3.7%) across state surveys and varied eightfold from 0.3% to 2.5% (median: 1.1%) across local surveys (Table 15).

Nationwide, 8.2% of students had used smokeless tobacco (chewing tobacco, snuff, or dip) on >1 of the 30 days preceding the survey (i.e., current smokeless tobacco use) (Table 16). Overall, male students (14.8%) were significantly more likely than female students (1.9%) to report current smokeless tobacco use. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Overall, white and Hispanic students (10.3% and 4.1%, respectively) were significantly more likely than black students (1.8%) to report current smokeless tobacco use, and white students (10.3%) were significantly more likely than Hispanic students (4.1%) to do so. These significant racial/ethnic differences were identified for male students. White female students (2.1%) were significantly more likely than black female students (0.7%) to report current smokeless tobacco use. Prevalence of current smokeless tobacco use varied sixfold from 2.9% to 18.1% (median: 8.2%) across state surveys and from 1.1% to 6.4% (median: 3%) across local surveys (Table 17).

Nationwide, 15.2% of students had smoked cigars, cigarillos, or little cigars on >1 of the 30 days preceding the survey (i.e., current cigar use) (Table 16). Overall, male students (22.1%) were significantly more likely than female students (8.5%) to report current cigar use. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. White male students (23.8%) were significantly more likely than black male students (15.8%) to report current cigar use. Overall, students in grade 12 (18%) were significantly more likely than students in grade 9 (12.5%) to report current cigar use. Prevalence of current cigar use varied fivefold from 4.1% to 19.3% (median: 14.8%) across state surveys and varied threefold from 5.1% to 16.3% (median: 12%) across local surveys (Table 17).

Nationwide, 33.9% of students had reported current cigarette use, current smokeless tobacco use, or current cigar use on >1 of the 30 days preceding the survey (i.e., current tobacco use) (Table 16). Male students (38.5%) were significantly more likely than female students (29.5%) to report current tobacco use. This significant sex difference was identified for white students and students in grades 11 and 12. Overall, white and Hispanic students (37.7% and 29.4%, respectively) were significantly more likely than black students (19.4%) to report current tobacco use, and white students (37.7%) were significantly more likely than Hispanic students (29.4%) to do so. White and Hispanic female students (32.3% and 27.2%, respectively) were significantly more likely than black female students (17.4%) to report current tobacco use, and white male students (43.4%) were significantly more likely than Hispanic and black male students (31.5% and 21.6%, respectively) to do so. Overall, students in grades 11 and 12 (36.1% and 41%, respectively) were significantly more likely than students in grade 9 (28.1%) to report current tobacco use, and students in grade 12 (41%) were significantly more likely than students in grade 10 (32.6%) to do so. Across state surveys, current tobacco use varied fourfold from 9.8% to 41.4% (median: 32.5%) (Table 17). Across local surveys, prevalence ranged from 14.7% to 27.1% (median: 19.1%).

Data regarding access to cigarettes are reported only for those students aged <18 years who reported current cigarette use. Nationwide, 19.1% of these students had purchased their cigarettes in a store or gas station during the 30 days preceding the survey (Table 18). Male students (25.7%) were significantly more likely than female students (13.1%) to have done so. This significant sex difference was identified for white students and students in all of the grade subpopulations. Overall, students in grades 10, 11, and 12 (19.1%, 28.7%, and 23.6%, respectively) were significantly more likely than students in grade 9 (8.8%) to have purchased cigarettes in a store or gas station, and students in grade 11 (28.7%) were significantly more likely than students in grade 10 (19.1%) to have done so. State prevalence varied ninefold from 4.4% to 39.1% (median: 18.6%), and local prevalence varied threefold from 14.2% to 46.4% (median: 26.9%) (Table 19).

Approximately two thirds of students (67.2%) who purchased or attempted to purchase cigarettes in a store or gas station during the 30 days preceding the survey had not been asked to show proof of age (Table 18). State prevalence ranged from 60% to 74.1% (median: 69.7%) (Table 19).

Alcohol and Other Drug Use

Nationwide, 78.2% of students had had >1 drinks of alcohol during their lifetime (i.e., lifetime alcohol use) (Table 20). Overall, Hispanic and white students (80.8% and 80.1%, respectively) were significantly more likely than black students (69.1%) to report lifetime alcohol use. This significant racial/ethnic difference was identified for both female and male students. Overall, students in grades 11 and 12 (80.4% and 85.1%, respectively) were significantly more likely than students in grade 9 (73.1%) to report lifetime alcohol use, and students in grade 12 (85.1%) were significantly more likely than students in grade 10 (76.3%) to do so. Prevalence of lifetime alcohol use ranged from 40.6% to 83.4% (median: 78.9%) across state surveys and from 57.7% to 81.1% (median: 73.9%) across local surveys (Table 21).

Nearly one half (47.1%) of students nationwide had had >1 drinks of alcohol on >1 of the 30 days preceding the survey (i.e., current alcohol use) (Figure 5) (Table 20). Male students in grade 11 (53.6%) were significantly more likely than female students in grade 11 (45.1%) to report current alcohol use. Overall, white and Hispanic students (50.4% and 49.2%, respectively) were significantly more likely than black students (32.7%) to report current alcohol use. This significant racial/ethnic difference was identified for female and male students. Overall, students in grades 11 and 12 (49.3% and 55.2%, respectively) were significantly more likely than students in grade 9 (41.1%) to report current alcohol use, and students in grade 12 (55.2%) were significantly more likely than students in grade 10 (45.2%) to report this behavior. Across state surveys, prevalence of current alcohol use varied threefold from 17.9% to 59.2% (median: 47.8%) (Table 21). Across local surveys, prevalence ranged from 28.3% to 45.4% (median: 39.8%).

Nationwide, 29.9% of students had had >5 drinks of alcohol on >1 occasions during the 30 days preceding the survey (i.e., episodic heavy drinking) (Table 20). Overall, male students (33.5%) were significantly more likely than female students (26.4%) to report episodic heavy drinking. This significant sex difference was identified for white and black students and students in grades 11 and 12. Overall, white and Hispanic students (34% and 30.1%, respectively) were significantly more likely than black students (11.1%) to report episodic heavy drinking. This significant racial/ethnic difference was identified for both female and male students. Overall, students in grades 11 and 12 (32.2% and 36.7%, respectively) were significantly more likely than students in grade 9 (24.5%) to report episodic heavy drinking, and students in grade 12 (36.7%) were significantly more likely than students in grade 10 (28.2%) to report this behavior. Prevalence of episodic heavy drinking varied fourfold from 10.9% to 41.5% (median: 30.3%) across state surveys and ranged from 10.6% to 26.1% (median: 19.9%) across local surveys (Table 21).

Nationwide, 42.4% of students had used marijuana during their lifetime (i.e., lifetime marijuana use) (Table 20). Overall, male students (46.5%) were significantly more likely than female students (38.4%) to report lifetime marijuana use. This significant sex difference was identified for white and Hispanic students and students in grades 9, 10, and 11. Overall, students in grades 10, 11, and 12 (41.7%, 47.2%, and 51.5%, respectively) were significantly more likely than students in grade 9 (32.7%) to report lifetime marijuana use, and students in grade 12 (51.5%) were significantly more likely than students in grade 10 (41.7%) to report this behavior. Prevalence of lifetime marijuana use ranged from 19.7% to 50.8% (median: 41.3%) across state surveys and from 29.7% to 49.7% (median: 40.6%) across local surveys (Table 21).

Approximately one fourth (23.9%) of students had used marijuana >1 times during the 30 days preceding the survey (i.e., current marijuana use) (Figure 6) (Table 20). Overall, male students (27.9%) were significantly more likely than female students (20%) to report current marijuana use. This significant sex difference was identified for white and black students and all grade subpopulations. Overall, students in grades 10, 11, and 12 (24.8%, 25.8%, and 26.9%, respectively) were significantly more likely than students in grade 9 (19.4%) to report current marijuana use. Prevalence of current marijuana use varied threefold from 9.7% to 33.2% (median: 23.4%) across state surveys and ranged from 16.8% to 28.7% (median: 20.4%) across local surveys (Table 21).

Nationwide, 9.4% of students had used a form of cocaine (e.g., powder, "crack,"** or "freebase"^††) during their lifetime (i.e., lifetime cocaine use) (Table 22). Overall, Hispanic and white students (14.9% and 9.9%, respectively) were significantly more likely than black students (2.1%) to report lifetime cocaine use, and Hispanic students (14.9%) were significantly more likely than white students (9.9%) to report this behavior. These significant racial/ethnic differences were identified for male students. Hispanic and white female students (13.1% and 9.2%, respectively) were significantly more likely than black female students (1.3%) to report lifetime cocaine use. Overall, students in grade 12 (12.1%) were significantly more likely than students in grade 9 (7.2%) to report lifetime cocaine use. Prevalence of lifetime cocaine use varied threefold from 4.1% to 13% (median: 8.3%) across state surveys and varied fourfold from 2.6% to 10.4% (median: 6.3%) across local surveys (Table 23).

Nationwide, 4.2% of students had used a form of cocaine >1 times during the 30 days preceding the survey (i.e., current cocaine use) (Table 22). Black male students (2.2%) were significantly more likely than black female students (0.4%) to report current cocaine use. Overall, Hispanic and white students (7.1% and 4.2%, respectively) were significantly more likely than black students (1.3%) to report current cocaine use, and Hispanic students (7.1%) were significantly more likely than white students (4.2%) to report this behavior. These significant racial/ethnic differences were identified for male students. Hispanic and white female students (5.9% and 3.9%, respectively) were significantly more likely than black female students (0.4%) to report current cocaine use. Prevalence of current cocaine use varied threefold from 2.1% to 6.3% (median: 3.7%) across state surveys and varied fivefold from 1.2% to 5.9% (median: 2.9%) across local surveys (Table 23).

Nationwide, 14.7% of students had sniffed glue, breathed the contents of aerosol spray cans, or inhaled any paints or sprays to get high during their lifetime (i.e., lifetime inhalant use) (Table 22). Overall, white and Hispanic students (16.3% and 15.2%, respectively) were significantly more likely than black students (5.8%) to report lifetime inhalant use. This significant racial/ethnic difference was identified for both female and male students. Across state surveys, prevalence of lifetime inhalant use ranged from 9.9% to 16.4% (median: 13.5%) (Table 23). Across local surveys, prevalence varied threefold from 6.1% to 17.2% (median: 8.7%).

Nationwide, 4.7% of students had used inhalants >1 times during the 30 days preceding the survey (i.e., current inhalant use) (Table 22). Overall, Hispanic and white students (5.5% and 4.9%, respectively) were significantly more likely than black students (2.6%) to report current inhalant use. White male students (5.4%) were significantly more likely than black male students (2.7%) to report current inhalant use. Overall, students in grades 9 and 10 (6.2% and 4.8%) were significantly more likely than students in grade 12 (2.9%) to report current inhalant use. Prevalence of current inhalant use ranged from 2.3% to 5.6% (median: 4.2%) across state surveys and varied threefold from 1.8% to 4.8% (median: 3.3%) across local surveys (Table 23).

Nationwide, 3.1% of students had used heroin during their lifetime (i.e., lifetime heroin use) (Table 24). Overall, male students (3.8%) were significantly more likely than female students (2.5%) to report lifetime heroin use. This significant sex difference was identified for white and black students. Overall, white and Hispanic students (3.3% and 3.1%, respectively) were significantly more likely than black students (1.7%) to report lifetime heroin use. This significant racial/ethnic difference was identified for female students. Prevalence of heroin use varied threefold from 1.4% to 4.3% (median: 3%) across state surveys and varied fivefold from 0.9% to 4.6% (median: 2.9%) across local surveys (Table 25).

Nationwide, 9.8% of students had used methamphetamines during their lifetime (i.e., lifetime methamphetamine use) (Table 24). Overall, white and Hispanic students (11.4% and 9.1%, respectively) were significantly more likely than black students (2.1%) to report lifetime methamphetamine use. This significant racial/ethnic difference was identified for both female and male students. Lifetime methamphetamine use varied threefold from 5.3% to 15.6% (median: 7.9%) across state surveys and varied threefold from 2.8% to 8.6% (median: 5.2%) across local surveys (Table 25).

Nationwide, 5% of students had used illegal steroids (i.e., without a doctor's prescription) during their lifetime (i.e., lifetime steroid use) (Table 24). Overall, male students (6%) were significantly more likely than female students (3.9%) to report lifetime steroid use. This significant sex difference was identified for white students and students in grade 12. Overall, white students (5.3%) were significantly more likely than black students (3.2%) to report lifetime steroid use. This significant racial/ethnic difference was identified for female students. Prevalence of lifetime illegal steroid use varied threefold from 2.6% to 6.9% (median: 5%) across state surveys and ranged from 2.3% to 5.7% (median: 4.5%) across local surveys (Table 25).

Nationwide, 2.3% of students had injected illegal drugs during their lifetime^§§ (i.e., lifetime injection-drug use) (Table 24). Overall, male students (3.1%) were significantly more likely than female students (1.6%) to report lifetime injection-drug use. This significant sex difference was identified for white and black students and for students in grade 12. Prevalence varied sixfold from 1.1% to 6.9% (median: 2.3%) across state surveys and varied fourfold from 0.8% to 3.2% (median: 2.2%) across local surveys (Table 25).

Age of Initiation of Risk Behaviors

Nationwide, 22.1% of students had smoked a whole cigarette before age 13 years (Table 26). Male students (24.5%) were significantly more likely than female students (19.8%) to have smoked a whole cigarette before age 13 years. Overall, white and Hispanic students (23.6% and 22.6%, respectively) were significantly more likely than black students (14.2%) to have smoked a whole cigarette before age 13 years. This significant racial/ethnic difference was identified for both female and male students. Overall, students in grade 9 (26.2%) were significantly more likely than students in grades 11 and 12 (18.5% and 19%, respectively) to have smoked a whole cigarette before age 13 years. Across state surveys, prevalence ranged from 12.2% to 28.1% (median: 23%) (Table 27). Prevalence across local surveys ranged from 11.1% to 21.2% (median: 17.3%).

Nationwide, 29.1% of students had first drunk alcohol (other than a few sips) before age 13 years (Table 26). Overall, male students (34.2%) were significantly more likely than female students (24.2%) to have drunk alcohol before age 13 years. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Overall, Hispanic students (33.7%) were significantly more likely than white students (28.4%) to have drunk alcohol before age 13 years. Hispanic male students (40.8%) were significantly more likely than white and black male students (33.3% and 32.4%, respectively) to report this behavior. Overall, students in grades 9 and 10 (39.7% and 28.8%, respectively) were significantly more likely than students in grades 11 and 12 (23.4% and 21.2%) to have drunk alcohol before age 13 years, and students in grade 9 (39.7%) were significantly more likely than students in grade 10 (28.8%) to have done so. Prevalence ranged from 21.7% to 35.1% (median: 29.1%) across state surveys and from 25.6% to 34.7% (median: 30.3%) across local surveys (Table 27).

One tenth (10.2%) of students nationwide had tried marijuana before age 13 years (Table 26). Overall, male students (13.2%) were significantly more likely than female students (7.5%) to have used marijuana before age 13 years. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Hispanic male students (16.5%) were significantly more likely than white male students (12%) to have tried marijuana before age 13 years. Overall, students in grades 9 and 10 (11.6% and 12.1%, respectively) were significantly more likely than students in grade 12 (7.8%) to have used marijuana before age 13 years, and students in grade 10 (12.1%) were significantly more likely than students in grade 11 (8.5%) to have done so. Prevalence varied fourfold from 4.5% to 17.8% (median: 11.1%) across state surveys (Table 27). Across local surveys, prevalence ranged from 7.5% to 15.6% (median: 11.5%).

Tobacco, Alcohol, and Other Drug Use on School Property

Nationwide, 9.9% of students had smoked cigarettes on school property on >1 of the 30 days preceding the survey (Table 28). Overall, male students (11.3%) were significantly more likely than female students (8.5%) to have smoked cigarettes on school property. This significant sex difference was identified for students in grade 9. Overall, white students (11.3%) were significantly more likely than Hispanic and black students (7.7% and 4.9%, respectively) to have smoked cigarettes on school property. This significant racial/ethnic difference was identified for male students. White and Hispanic female students (9.8% and 7.9%, respectively) were significantly more likely than black female students (2.8%) to report this behavior. Across state surveys, prevalence varied sixfold from 2.7% to 16% (median: 9.8%) (Table 29). Across local surveys, prevalence varied threefold from 3.5% to 11.1% (median: 6.3%).

Nationwide, 5% of students had used smokeless tobacco on school property on >1 of the 30 days preceding the survey (Table 28). Overall, male students (9.4%) were significantly more likely than female students (0.7%) to have used smokeless tobacco on school property. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Overall, white and Hispanic students (6.2% and 2.7%, respectively) were significantly more likely than black students (1.1%) to have used smokeless tobacco on school property, and white students (6.2%) were significantly more likely than Hispanic students (2.7%) to have done so. White male students (11.9%) were significantly more likely than Hispanic and black male students (4.3% and 2%, respectively) to report this behavior. Prevalence varied 13-fold from 0.9% to 11.5% (median: 4.5%) across state surveys (Table 29). Across local surveys, prevalence varied fivefold from 0.7% to 3.3% (median: 1.7%)

Nationwide, 4.9% of students had had >1 drinks of alcohol on school property on >1 of the 30 days preceding the survey (Table 28). Overall, male students (6.1%) were significantly more likely than female students (3.8%) to have drunk alcohol on school property. This significant sex difference was identified for white and black students and students in grades 11 and 12. Overall, Hispanic students (7%) were significantly more likely than white students (4.2%) to have drunk alcohol on school property, and Hispanic female students (7.1%) were significantly more likely than white and black female students (3.2% and 3.1%, respectively) to have done so. Across state surveys, prevalence varied threefold from 2.4% to 8.3% (median: 4.9%) (Table 29). Prevalence across local surveys varied threefold from 3.2% to 9.2% (median: 6.3%).

Nationwide, 5.4% of students had used marijuana on school property >1 times during the 30 days preceding the survey (Table 28). Overall, male students (8%) were significantly more likely than female students (2.9%) to have used marijuana on school property. This significant sex difference was identified for white and black students and students in all the grade subpopulations. Overall, Hispanic students (7.4%) were significantly more likely than white students (4.8%) to have used marijuana on school property. Hispanic female students (5.8%) were significantly more likely than black and white female students (2.3% and 2.2%, respectively) to report this behavior. Across state surveys, prevalence varied fourfold from 2.5% to 10.9% (median: 5.2%) (Table 29). Prevalence across local surveys ranged from 5.1% to 10.3% (median: 6%).

Nationwide, 28.5% of students had been offered, sold, or given an illegal drug on school property during the 12 months preceding the survey (Table 28). Overall, male students (34.6%) were significantly more likely than female students (22.7%) to have been offered, sold, or given an illegal drug on school property. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Overall, Hispanic students (34.2%) were significantly more likely than white and black students (28.3% and 21.9%, respectively) to have been offered, sold, or given an illegal drug on school property, and white students (28.3%) were significantly more likely than black students (21.9%) to report this behavior. Hispanic female students (28.7%) were significantly more likely than white and black female students (22.7% and 16.2%, respectively) to have been offered, sold, or given an illegal drug on school property, and white female students (22.7%) were significantly more likely than black female students (16.2%) to report this behavior. Hispanic male students (39.8%) were significantly more likely than black male students (27.9%) to have been offered, sold, or given an illegal drug on school property. Prevalence across state surveys ranged from 16.9% to 36% (median: 27.6%) (Table 29). Prevalence across local surveys varied threefold from 13.9% to 41.2% (median: 30.7%).

Sexual Behaviors That Contribute to Unintended Pregnancy and STDs, Including HIV Infection

Nationwide, 45.6% of students had had sexual intercourse during their lifetime (Figure 7) (Table 30). Overall, male students (48.5%) were significantly more likely than female students (42.9%) to have had sexual intercourse. This significant sex difference was identified for black students and students in grade 9. Overall, black students (60.8%) were significantly more likely than Hispanic and white students (48.4% and 43.2%, respectively) to have had sexual intercourse. Black female students (53.4%) were significantly more likely than white female students (41.3%) to have had sexual intercourse. Black and Hispanic male students (68.8% and 53%, respectively) were significantly more likely than white male students (45.1%) to have had sexual intercourse, and black male students (68.8%) were significantly more likely than Hispanic male students (53%) to report this behavior. Overall, students in grades 11 and 12 (51.9% and 60.5%, respectively) were significantly more likely than students in grades 9 and 10 (34.4% and 40.8%, respectively) to have had sexual intercourse, and students in grade 12 (60.5%) were significantly more likely than students in grade 11 (51.9%) to report this behavior. Prevalence of lifetime sexual intercourse ranged from 32.7% to 60.6% (median: 44.3%) across state surveys and from 29.8% to 61.6% (median: 50.8%) across local surveys (Table 31).

Nationwide, 6.6% of students had initiated sexual intercourse before age 13 years (Table 30). Overall, male students (9.3%) were significantly more likely than female students (4%) to have initiated sexual intercourse before age 13 years. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Overall, black students (16.3%) were significantly more likely than Hispanic and white students (7.6% and 4.7%, respectively) to have initiated sexual intercourse before age 13 years. This significant racial/ethnic difference was identified for male students. Hispanic male students (11.4%) were significantly more likely than white male students (6.2%) to report this behavior. Black female students (7.6%) were significantly more likely than white female students (3.3%) to have initiated sexual intercourse before age 13 years. Overall, students in grades 9 and 10 (9.2% and 7.5%, respectively) were significantly more likely than students in grades 11 and 12 (4.6% and 3.6%, respectively) to have initiated sexual intercourse before age 13 years. Across state surveys, prevalence varied fivefold from 3.1% to 14% (median: 5.3%) (Table 31). Prevalence varied threefold from 5.2% to 17.2% (median: 10.9%) across local surveys.

Nationwide, 14.2% of students had had sexual intercourse during their lifetime with >4 sex partners (Table 30). Male students (17.2%) were significantly more likely than female students (11.4%) to have had >4 sex partners. This significant sex difference was identified for black and Hispanic students and students in grades 9, 10, and 11. Overall, black students (26.6%) were significantly more likely than Hispanic and white students (14.9% and 12%, respectively) to report this behavior. Black female students (15.6%) were significantly more likely than Hispanic female students (9.5%) to have had >4 sex partners. Black male students (38.7%) were significantly more likely than Hispanic and white male students (20.6% and 12.8%, respectively) to have had >4 sex partners, and Hispanic male students (20.6%) were significantly more likely than white male students (12.8%) to report this behavior. Overall, students in grade 11 (15.2%) were significantly more likely than students in grade 9 (9.6%) to have had >4 sexual partners, and students in grade 12 (21.6%) were significantly more likely than students in grades 9, 10, and 11 (9.6%, 12.6%, and 15.2%, respectively) to report this behavior. Prevalence varied threefold from 8.4% to 25.5% (median: 13.2%) across state surveys (Table 31). Across local surveys, prevalence varied threefold from 7.8% to 25.9% (median: 18.9%).

One third (33.4%) of students nationwide had had sexual intercourse during the 3 months preceding the survey (i.e., currently sexually active) (Table 30). Black male students (52.3%) were significantly more likely than black female students (39.5%) to be currently sexually active. Overall, black students (45.6%) were significantly more likely than Hispanic and white students (35.9% and 31.3%, respectively) to be currently sexually active. This significant racial/ethnic difference was identified for male students, and Hispanic male students (37.3%) were significantly more likely than white male students (30%) to report this behavior. Overall, students in grades 10, 11, and 12 (29.7%, 38.1%, and 47.9%, respectively) were significantly more likely than students in grade 9 (22.7%) to be currently sexually active; students in grades 11 and 12 (38.1% and 47.9%, respectively) were significantly more likely than students in grade 10 (29.7%) to report this behavior; and students in grade 12 (47.9%) were significantly more likely than students in grade 11 (38.1%) to report this behavior. Prevalence ranged from 23% to 44.9% (median: 33.3%) across state surveys (Table 31). Across local surveys, prevalence ranged from 19.8% to 45.1% (median: 35.9%).

Nationwide, 86.1% of students had never had sexual intercourse, had sexual intercourse but not during the 3 months preceding the survey, or had used a condom the last time they had sexual intercourse during the 3 months preceding the survey (i.e., responsible sexual behavior) (Table 30). Overall, male students (88.5%) were significantly more likely than female students (83.9%) to have engaged in responsible sexual behavior. This significant sex difference was identified for white students and students in grades 10 and 12. Overall, students in grade 9 (92.8%) were significantly more likely than students in grades 10, 11, and 12 (88.3%, 84.5%, and 75.8%, respectively) to have engaged in responsible sexual behavior; students in grade 10 (88.3%) were significantly more likely than students in grades 11 and 12 (84.5% and 75.8%, respectively) to report this behavior; and students in grade 11 (84.5%) were significantly more likely than students in grade 12 (75.8%) to report this behavior. Prevalence of responsible sexual behavior ranged from 83.7% to 92.8% (median: 87.1%) across state surveys and from 83.4% to 92.8% (median: 89.1%) across local surveys (Table 31).

Among the 33.4% of currently sexually active students nationwide, 57.9% reported that either they or their partner had used a condom during last sexual intercourse (Table 32). Overall, male students (65.1%) were significantly more likely than female students (51.3%) to report condom use. This significant sex difference was identified for white and black students and students in grades 10, 11, and 12. Overall, black students (67.1%) were significantly more likely than white and Hispanic students (56.8% and 53.5%, respectively) to report condom use. This significant racial/ethnic difference was identified for both female and male students. Overall, students in grades 9, 10, and 11 (67.5%, 60.1%, and 58.9%, respectively) were significantly more likely than students in grade 12 (49.3%) to report condom use, and students in grade 9 (67.5%) were significantly more likely than students in grade 11 (58.9%) to report condom use. Prevalence ranged from 45.5% to 68.3% (median: 59.2%) across state surveys and from 53.3% to 76.1% (median: 65.1%) across local surveys (Table 33).

Among the 33.4% of currently sexually active students nationwide, 18.2% reported that either they or their partner had used birth control pills before last sexual intercourse (Table 32). Overall, female students (21.1%) were significantly more likely than male students (14.9%) to report birth control pill use. This significant sex difference was identified for white students and students in grade 11. Overall, white students (23.4%) were significantly more likely than Hispanic and black students (9.6% and 7.9%, respectively) to report birth control pill use. This significant racial/ethnic difference was identified for both female and male students. Overall, students in grades 10, 11, and 12 (15.8%, 18.6%, and 26.3%, respectively) were significantly more likely than students in grade 9 (7.6%) to report birth control pill use, and students in grade 12 (26.3%) were significantly more likely than students in grades 10 and 11 (15.8% and 18.6%, respectively) to report this behavior. Prevalence varied threefold from 10.8% to 36.1% (median: 19.5%) across state surveys (Table 33). Across local surveys, prevalence ranged from 6.4% to 16.7% (median: 9.4%).

Among the 33.4% of currently sexually active students nationwide, 25.6% had used alcohol or drugs at last sexual intercourse (Table 32). Male students (30.9%) were significantly more likely than female students (20.7%) to have used alcohol or drugs at last sexual intercourse. This significant sex difference was identified for white and black students and students in grades 10, 11, and 12. Overall, white and Hispanic students (27.8% and 24.1%, respectively) were significantly more likely than black students (17.8%) to have used alcohol or drugs at last sexual intercourse, and this significant racial/ethnic difference was identified for female students. Prevalence ranged from 20.2% to 33.5% (median: 24.9%) across state surveys and from 13.5% to 26.4% (median: 18.3%) across local surveys (Table 33).

Nationwide, 4.7% of students reported that they had been pregnant or had gotten someone else pregnant (Table 32). White female students (4%) were significantly more likely than white male students (2.5%) and female students in grade 12 (9.4%) were significantly more likely than male students in grade 12 (4.8%) to have been pregnant or to have gotten someone pregnant. Overall, black and Hispanic students (11.4% and 5.7%, respectively) were significantly more likely than white students (3.3%) to have been pregnant or to have gotten someone pregnant; black students (11.4%) were significantly more likely than Hispanic students (5.7%) to report this information. This significant racial/ethnic difference was identified for male students. Black female students (11.9%) were significantly more likely than Hispanic and white female students (6.2% and 4%, respectively) to have been pregnant. Overall, students in grade 12 (7.1%) were significantly more likely than students in grades 9, 10, and 11 (3.2%, 4.4%, and 4.8%, respectively) to have been pregnant or to have gotten someone pregnant. Prevalence varied threefold from 2.2% to 7.4% (median: 4.2%) across state surveys and varied fourfold from 2.3% to 10.3% (median: 6.3%) across local surveys (Table 33).

Nationwide, 89% of students reported being taught in school about acquired immunodeficiency syndrome (AIDS) or HIV infection (Table 32). Overall, white students (91.1%) were significantly more likely than black and Hispanic students (86.1% and 80.5%, respectively) to have been taught about AIDS or HIV infection in school. This significant racial/ethnic difference was identified for male students. White female students (90.4%) were significantly more likely than Hispanic female students (81.4%) to have been taught about AIDS or HIV infection in school. Overall, students in grades 11 and 12 (90.5% and 90.2%, respectively) were significantly more likely than students in grade 9 (86.7%) to have been taught about AIDS or HIV infection in school. Across state surveys, prevalence ranged from 79.8% to 93.8% (median: 88.6%) (Table 33). Prevalence ranged from 81% to 91% (median: 86.7%) across local surveys.

Dietary Behaviors

Nationwide, 13.6% of students were at risk for becoming overweight (Table 34). Overall, male students (15.5%) were significantly more likely than female students (11.7%) to be at risk for becoming overweight. This significant sex difference was identified for white students and students in grades 9 and 10. Overall, black and Hispanic students (17.8% and 16.3%, respectively) were significantly more likely than white students (12.5%) to be at risk for becoming overweight. This significant racial/ethnic difference was identified for female students. Overall, students in grade 9 (15.7%) were significantly more likely than students in grade 12 (11.8%) to be at risk for becoming overweight. Prevalence of being at risk for becoming overweight ranged from 8.4% to 15.9% (median: 14%) across state surveys and from 11.5% to 18.7% (median: 16.1%) across local surveys (Table 35).

Nationwide, 10.5% of students were overweight (Figure 8) (Table 34). Overall, male students (14.2%) were significantly more likely than female students (6.9%) to be overweight. This significant sex difference was identified for white and Hispanic students and students in all grade subpopulations. Overall, black and Hispanic students (16% and 15.1%, respectively) were significantly more likely than white students (8.8%) to be overweight. This significant racial/ethnic difference was identified for both female and male students. Black female students (14.6%) were significantly more likely than Hispanic female students (8.8%) to be overweight. Across state surveys, prevalence of being overweight ranged from 6.1% to 14.2% (median: 10.4%) (Table 35). Across local surveys, prevalence ranged from 7.8% to 18% (median: 12.5%).

Nationwide, 29.2% of students thought they were overweight (Table 34). Overall, female students (34.9%) were significantly more likely than male students (23.3%) to consider themselves overweight. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Overall, Hispanic students (34.8%) were significantly more likely than white and black students (29.2% and 25.7%, respectively) to consider themselves overweight, and white students (29.2%) were significantly more likely than black students (25.7%) to consider themselves overweight. This significant racial/ethnic difference was identified for male students. Hispanic female students (40.3%) were significantly more likely than black female students (32.3%) to consider themselves overweight. Across state surveys, prevalence ranged from 26.4% to 33.6% (median: 30.7%) (Table 35). Across local surveys, prevalence ranged from 18.7% to 32.9% (median: 28.5%).

Nationwide, 46% of students were trying to lose weight during the 30 days preceding the survey (Table 34). Overall, female students (62.3%) were significantly more likely than male students (28.8%) to be trying to lose weight. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Overall, Hispanic and white students (51.5% and 47.1%, respectively) were significantly more likely than black students (36.9%) to be trying to lose weight. This significant racial/ethnic difference was identified for female students. Hispanic male students (39.1%) were significantly more likely than white and black male students (27.9% and 23.6%, respectively) to report this. Prevalence ranged from 40.6% to 51.5% (median: 44.5%) across state surveys and from 34.7% to 50.1% (median: 41.5%) across local surveys (Table 35).

Nationwide, 21.4% of students had eaten >5 serving per day of fruits and vegetables^¶¶ during the 7 days preceding the survey (Figure 9) (Table 36). Overall, male students (23.3%) were significantly more likely than female students (19.7%) to have eaten >5 servings per day of fruits and vegetables. This significant sex difference was identified for black students. Overall, black students (24.5%) were significantly more likely than white students (20.2%) to have eaten >5 servings per day of fruits and vegetables, and this significant racial/ethnic difference was identified for male students. Prevalence ranged from 13.1% to 27.4% (median: 19.9%) across state surveys and from 14.9% to 29.5% (median: 21.6%) across local surveys (Table 37).

Overall, 16.4% of students drank >3 glasses per day of milk during the 7 days preceding the survey (Table 36). Male students (22.3%) were significantly more likely than female students (10.9%) to have drunk >3 glasses per day of milk. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Overall, white students (18.1%) were significantly more likely than Hispanic and black students (13.8% and 12%, respectively) to have drunk >3 glasses per day of milk, and this significant racial/ethnic difference was identified for male students. White female students (12.1%) were significantly more likely than black female students (8.1%) to have drunk >3 glasses per day of milk. Across state surveys, prevalence varied threefold from 10.5% to 29.7% (median: 18.4%) (Table 37). Prevalence varied fourfold from 5% to 18.1% (median: 11.4%) across local surveys.

Nationwide, 59.9% of students had exercised to lose weight or to avoid gaining weight during the 30 days preceding the survey (Table 38). Overall, female students (68.4%) were significantly more likely than male students (51%) to have exercised to lose weight or to avoid gaining weight. This significant sex difference was identified for white and Hispanic students and students in all the grade subpopulations. Overall, white and Hispanic students (61.9% and 61.5%, respectively) were significantly more likely than black students (50.1%) to have exercised to lose weight or to avoid gaining weight. This significant racial/ethnic difference was identified for female students. White female students (72.5%) were significantly more likely than Hispanic female students (66.2%) to have exercised to lose weight or to avoid gaining weight, and Hispanic male students (56.8%) were significantly more likely than white and black male students (50.9% and 46.6%, respectively) to report this behavior. Overall, students in grade 9 (64.2%) were significantly more likely than students in grades 11 and 12 (56.3% and 57.2%, respectively) to have exercised to lose weight or to avoid gaining weight. Prevalence ranged from 53.2% to 64.5% (median: 59.3%) across state surveys and from 45.1% to 66.3% (median: 54.6%) across local surveys (Table 39).

Nationwide, 43.8% of students had eaten less food, fewer calories, or foods low in fat to lose weight or to avoid gaining weight during the 30 days preceding the survey (Table 38). Overall, female students (58.6%) were significantly more likely than male students (28.2%) to have eaten less food, fewer calories, or foods low in fat to lose weight or to avoid gaining weight. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Overall, white and Hispanic students (45.9% and 44.9%, respectively) were significantly more likely than black students (32.5%) to have eaten less food, fewer calories, or foods low in fat to lose weight or to avoid gaining weight. This significant racial/ethnic difference was identified for female students. White female students (63.1%) were significantly more likely than Hispanic female students (56.5%) to have eaten less food, fewer calories, or foods low in fat to lose weight or to avoid gaining weight, and Hispanic male students (32.7%) were significantly more likely than black male students (24.5%) to report this behavior. Across state surveys, prevalence ranged from 35.9% to 46.4% (median: 40.9%) (Table 39). Prevalence ranged from 29.5% to 42.4% (median: 37.5%) across local surveys.

Nationwide, 13.5% of students had gone without eating for >24 hours to lose weight or to avoid gaining weight (Table 38). Overall, female students (19.1%) were significantly more likely than male students (7.6%) to have gone without eating for >24 hours to lose weight or to avoid gaining weight. This significant sex difference was identified for white and Hispanic students and all the grade subpopulations. Hispanic and white female students (23.1% and 19.7%, respectively) were significantly more likely than black female students (15.2%) to have gone without eating for >24 hours to lose weight or to avoid gaining weight. Overall, students in grade 9 (15.4%) were significantly more likely than students in grades 11 and 12 (11.5% and 11.5%, respectively) to report this behavior. Prevalence ranged from 10.3% to 16.2% (median: 13.5%) across state surveys and from 8.1% to 16.1% (median: 13.4%) across local surveys (Table 39).

One tenth (9.2%) of students nationwide had taken diet pills, powders, or liquids without a doctor's advice to lose weight or to avoid gaining weight (Table 38). Overall, female students (12.6%) were significantly more likely than male students (5.5%) to have taken diet pills, powders, or liquids without a doctor's advice to lose weight or to avoid gaining weight. This significant sex difference was identified for white and Hispanic students and all the grade subpopulations. Overall, Hispanic and white students (10.1% and 9.5%, respectively) were significantly more likely than black students (6%) to report this behavior. This significant racial/ethnic difference was identified for female students. Across state surveys, prevalence varied threefold from 4.9% to 13% (median: 8.5%) (Table 39). Prevalence varied threefold from 3.2% to 10.6% (median: 6.9%) across local surveys.

Nationwide, 5.4% of students had vomited or taken laxatives to lose weight or to avoid gaining weight (Table 38). Overall, female students (7.8%) were significantly more likely than male students (2.9%) to have vomited or taken laxatives to lose weight or to avoid gaining weight. This significant sex difference was identified for white and Hispanic students and students in all the grade subpopulations. Overall, Hispanic students (7.2%) were significantly more likely than black students (4%) to report this behavior. Hispanic and white female students (10.8% and 8.2%, respectively) were significantly more likely than black female students (4.2%) to report this behavior. Prevalence ranged from 3.6% to 7.6% (median: 5.6%) across state surveys and varied threefold from 2.5% to 8.5% (median: 5.5%) across local surveys (Table 39).

Physical Activity

Approximately two thirds (64.6%) of students nationwide had participated in activities that made them sweat and breathe hard for >20 minutes on >3 of the 7 days preceding the survey (i.e., sufficient vigorous physical activity) (Table 40). Overall, male students (72.6%) were significantly more likely than female students (57%) to report sufficient vigorous physical activity. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Overall, white students (66.5%) were significantly more likely than Hispanic and black students (60.5% and 59.7%, respectively) to report sufficient vigorous physical activity. This significant racial/ethnic difference was identified for female students. White male students (73.7%) were significantly more likely than Hispanic male students (68.8%) to report sufficient vigorous physical activity. Overall, students in grades 9, 10, and 11 (71.9%, 67%, and 61.3%, respectively) were significantly more likely than students in grade 12 (55.5%) to report sufficient vigorous physical activity. Students in grades 9 and 10 (71.9% and 67%, respectively) were significantly more likely than students in grade 11 (61.3%) to report sufficient vigorous physical activity, and students in grade 9 (71.9%) were significantly more likely than students in grade 10 (67%) to report this behavior. Prevalence of sufficient vigorous physical activity ranged from 54.9% to 74.1% (median: 64.3%) across state surveys and from 40.7% to 65% (median: 54.9%) across local surveys (Table 41).

One fourth (25.5%) of students nationwide had participated in activities that did not make them sweat or breathe hard for >30 minutes on >5 of the 7 days preceding the survey (i.e., sufficient moderate physical activity) (Table 40). Overall, male students (28.4%) were significantly more likely than female students (22.8%) to report sufficient moderate physical activity. This significant sex difference was identified for all the racial/ethnic subpopulations and students in grades 10 and 11. Overall, white students (27.3%) were significantly more likely than Hispanic and black students (22.1% and 20.1%, respectively) to report sufficient moderate physical activity. This significant racial/ethnic difference was identified for female students. White male students (29.8%) were significantly more likely than black male students (23.7%) to report sufficient moderate physical activity. Across state surveys, prevalence of sufficient moderate physical activity ranged from 19.2% to 31% (median: 25.4%) (Table 41). Across local surveys, prevalence ranged from 12.3% to 26.5% (median: 21.6%).

Nationwide, 31.2% of students had not participated in vigorous physical activity for >20 minutes on >3 of the 7 days preceding the survey and had not participated in moderate physical activity for >30 minutes on >5 of the 7 days preceding the survey (i.e., insufficient amount of physical activity) (Table 40). Overall, female students (37.9%) were significantly more likely than male students (24.2%) to report an insufficient amount of physical activity. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Overall, black and Hispanic students (36.4% and 35.4%, respectively) were significantly more likely than white students (29.3%) to report an insufficient amount of physical activity. This significant racial/ethnic difference was identified for female students. Overall, students in grades 10, 11, and 12 (29.6%, 34.4%, and 38.9%, respectively) were significantly more likely than students in grade 9 (24.3%) to report an insufficient amount of physical activity. Students in grades 11 and 12 (34.4% and 38.9%, respectively) were significantly more likely than students in grade 10 (29.6%) to report this information. Prevalence of insufficient physical activity ranged from 22% to 41% (median: 31.2%) across state surveys and from 30.5% to 56.7% (median: 41.1%) across local surveys (Table 41).

One tenth (9.5%) of students nationwide had not participated in either vigorous physical activity for >20 minutes or moderate physical activity for >30 minutes on any of the 7 days preceding the survey (i.e., no vigorous or moderate physical activity) (Table 40). Overall, female students (11.6%) were significantly more likely than male students (7.2%) to report no vigorous or moderate physical activity. This significant sex difference was identified for white and black students and students in grades 11 and 12. Overall, black and Hispanic students (12.9% and 11.2%, respectively) were significantly more likely than white students (8.2%) to report no vigorous or moderate physical activity. Black female students (16.9%) were significantly more likely than white female students (10.2%), and Hispanic male students (9.3%) were significantly more likely than white male students (6.2%) to report this information. Overall, students in grades 11 and 12 (11.1% and 12%, respectively) were significantly more likely than students in grades 9 and 10 (7.1% and 8.5%, respectively) to report no vigorous or moderate physical activity. Across state surveys, prevalence varied fourfold from 4.2% to 15.6% (median: 9.2%) (Table 41). Across local surveys, prevalence ranged from 10.1% to 25.3% (median: 13.1%).

Nationwide, 51.7% of students were enrolled in a physical education (PE) class (Table 42). Black male students (67.4%) were significantly more likely than white male students (52%) to be enrolled in a PE class. Overall, students in grades 9 and 10 (73.7% and 54.1%, respectively) were significantly more likely than students in grades 11 and 12 (39.1% and 31.3%, respectively) to be enrolled in a PE class, and students in grade 9 (73.7%) were significantly more likely than students in grade 10 (54.1%) to report this. Across state surveys, prevalence of being enrolled in a PE class varied fourfold from 22.1% to 93.6% (median: 47.1%) (Table 43). Across local surveys, prevalence varied threefold from 33.3% to 85.6% (median: 56%).

Approximately one third (32.2%) of students nationwide attended PE class daily (Figure 10) (Table 42). Male students in grade 11 (30%) were significantly more likely than female students in grade 11 (15.6%) to have attended PE class daily, and male students in grade 12 (26.1%) were significantly more likely than female students in grade 12 (14.7%) to report this behavior. Overall, students in grade 9 (48.7%) were significantly more likely than students in grades 10, 11, and 12 (31.6%, 22.8%, and 20.3% respectively) to have attended PE class daily, and students in grade 10 (31.6%) were significantly more likely than students in grade 12 (20.3%) to report this behavior. Across state surveys, prevalence varied 20-fold from 3.6% to 70.6% (median: 28.1%) (Table 43). Prevalence varied sixfold across local surveys from 10.3% to 57.1% (median: 23.8%).

Among the 51.7% of students enrolled in PE class, 83.4% exercised >20 minutes during an average PE class (Table 42). Overall, male students (87.7%) were significantly more likely than female students (78.8%) to have exercised >20 minutes during an average PE class. This significant sex difference was identified for white and black students and students in grades 10, 11, and 12. Overall, white students (85.2%) were significantly more likely than black students (76.4%) to have exercised >20 minutes during an average PE class. This significant racial/ethnic difference was identified for both female and male students. Prevalence ranged from 71.9% to 91.5% (median: 83.6%) across state surveys and from 54.9% to 84.9% (median: 75.1%) across local surveys (Table 43).

Nationwide, 55.2% of students had played on >1 sports teams during the 12 months preceding the survey (Table 42). Overall, male students (60.9%) were significantly more likely than female students (49.9%) to have played on sports teams. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Overall, white students (57.4%) were significantly more likely than Hispanic students (48.8%) to have played on sports teams. White female students (53.3%) were significantly more likely than black and Hispanic female students (41.6% and 40.1%, respectively) to have played on sports teams. Overall, students in grades 9, 10, and 11 (59.9%, 56.2%, and 54.5%, respectively) were significantly more likely than students in grade 12 (48.5%) to have played on sports teams, and students in grade 9 (59.9%) were significantly more likely than students in grade 11 (54.5%) to report this behavior. Prevalence of having played on sports teams ranged from 49.3% to 68.3% (median: 58.6%) across state surveys and from 41.4% to 55.5% (median: 48%) across local surveys (Table 43).

Nationwide, 53.4% of students had done strengthening exercises (e.g., push-ups, sit-ups, and weightlifting) on >3 of the 7 days preceding the survey (Table 44). Overall, male students (62.8%) were significantly more likely than female students (44.5%) to have participated in strengthening activities. This significant sex difference was identified for all the racial/ethnic and grade subpopulations. Overall, white students (54.8%) were significantly more likely than black students (47.9%) to have participated in strengthening activities. This significant racial/ethnic difference was identified for female students. Overall, students in grade 9 (58.7%) were significantly more likely than students in grades 11 and 12 (51.1% and 48%, respectively) to have participated in strengthening activities, and students in grade 10 (53.9%) were significantly more likely than students in grade 12 (48%) to report this behavior. Across state surveys, prevalence ranged from 43.7% to 59.2% (median: 51.1%) (Table 45). Across local surveys, prevalence ranged from 34.1% to 52.4% (median: 44.2%).

Nationwide, 38.3% of students had watched television >3 hours per day during an average school day (Table 44). Overall, male students (41.8%) were significantly more likely than female students (35%) to have watched television for >3 hours per day. This significant sex difference was identified for white students and students in grade 9. Overall, black and Hispanic students (68.9% and 47.8%, respectively) were significantly more likely than white students (31%) to have watched television for >3 hours per day, and black students (68.9%) were significantly more likely than Hispanic students (47.8%) to report this behavior. This significant racial/ethnic difference was identified for both female and male students. Overall, students in grade 9 (45.3%) were significantly more likely than students in grades 11 and 12 (34.7% and 31.3%, respectively) to have watched television for >3 hours per day, and students in grade 10 (39.2%) were significantly more likely than students in grade 12 (31.3%) to report this behavior. Prevalence varied threefold from 17.7% to 54.7% (median: 32.4%) across state surveys and from 41.8% to 66.8% (median: 52.6%) across local surveys (Table 45).

Trends During 1991--2001

During 1991--2001, significant decreases occurred in the percentage of students who never or rarely wore seatbelts (25.9%--14.1%), rode with a driver who had been drinking alcohol (39.9%--30.7%), participated in a physical fight (42.5%--33.2%), seriously considered suicide (29%--19%), and planned to attempt suicide (18.6%--14.8). The percentage of students who carried a weapon decreased significantly from 1991--1997 (26.1%--18.3%) and then remained constant from 1997--2001 (18.3%--17.4%). The percentage of students who reported lifetime and current marijuana use increased significantly from 1991--1997 (31.3%--47.1% and 14.7%--26.2%, respectively) and then decreased significantly from 1997--2001 (47.1%--42.4% and 26.2%--23.9%, respectively). The percentage of students who reported lifetime and current cocaine use increased significantly from 1991--2001 (5.9%--9.4% and 1.7%--4.2%, respectively).

During 1991--2001, the percentage of students who ever had sexual intercourse and had sexual intercourse with >4 partners decreased significantly (54.1%--45.6% and 18.7%--14.2%, respectively). During 1991--1999, the percentage of currently sexually active students who used a condom at last sexual intercourse increased significantly (46.2%--58%) and then leveled off by 2001 (58%--57.9%).

The percentage of students who reported current cigarette use and frequent cigarette use increased significantly from 1991--1997 (27.5%--36.4% and 12.7%--16.7%, respectively) and then decreased significantly from 1997--2001 (36.4%--28.5% and 16.7%--13.8%, respectively). During 1995--2001, current smokeless tobacco use decreased significantly (11.4%--8.2%), and from 1997--2001, current cigar use decreased significantly (22%--15.2%). While the percentage of students enrolled in PE class remained constant from 1991--2001 (48.9%--51.7%), the percentage of students enrolled in daily PE classes decreased significantly from 1991--1995 (41.6%--25.4%) and then increased significantly from 1995--2001 (25.4%--32.2%).

Discussion

Trend analysis of selected risk behaviors indicated increases and decreases in the risk for unintentional injuries and violence and decreases in the risk for HIV infection, other STDs, unintended pregnancy, and chronic diseases. Nonetheless, too many high school students nationwide continue to practice behaviors that place them at risk for serious acute and chronic health problems. Certain risk behaviors are more likely to be found among particular subpopulations of students. The association between race/ethnicity and certain risk behaviors might be attenuated by controlling for socioeconomic status (8). However, underlying causes (e.g., economic factors, education levels, or cultural influences) of subgroup differences could not be identified in this analysis. Additional research is needed to assess the effect of specific educational, socioeconomic, cultural, and racial/ethnic factors on the prevalence of health-risk behaviors among youth.

Considerable variation in prevalence of risk behaviors also occurs from state to state and from city to city. For example, across state surveys, a fivefold variation or greater was identified for the following risk behaviors:

Across local surveys, a similar fivefold variation was identified for the following risk behaviors:

These variations might occur, in part, because of differences in state and local laws and policies, enforcement practices, access to illegal drugs, availability of effective interventions, prevailing behavioral norms, demographic characteristics of the population, and adult practices. However, further research is needed to obtain increased understanding of the effect of these factors on the prevalence of risk behaviors.

Healthy People 2010

The national YRBS is the primary source of data to measure 15 Healthy People 2010 objectives and three Leading Health Indicators (9). The Healthy People 2010 objectives provide a comprehensive agenda for improving the health of all persons in the United States during the first decade of the 21st century. This report provides the 2010 target and data from the 2001 national YRBS for each 2010 objective (Table 46).

Limitations

The findings in this report are subject to several limitations. First, these data apply only to youth who attend school and, therefore, are not representative of all persons in this age group. Nationwide, approximately 5% of persons aged 16--17 years were not enrolled in a high school program and had not completed high school (10). Second, the extent of underreporting or overreporting of behaviors cannot be determined, although the survey questions demonstrate good test-retest reliability (11). Third, BMI is calculated based on self-reported height and weight and, therefore, tends to underestimate the prevalence of overweight and at risk for overweight. Fourth, unweighted state and local data represent only those students who participated in the survey and are not generalizable to the entire jurisdiction. Fifth, data are not available from all 50 states.

Conclusion

Uses of YRBS Data

The national YRBS data are used routinely by CDC and other federal agencies. The following are examples of how CDC uses YRBS data:

References

* In this report, black students refer to black or African American, non-Hispanic students.

^† In this report, Hispanic students refer to Hispanic or Latino students of any race.

^¶ A questionnaire that fails quality control has fewer than 20 valid items after editing.

^†† A process whereby cocaine is dissolved in ether or sodium hydroxide and the precipitate filtered off.

^§§ Students were classified as injection-drug users only if they a) reported injecting-drug use not prescribed by a physician and b) answered one or more times to any of the following questions: "During your life, how many times have you used any form of cocaine including powder, crack, or freebase?" "During your life, how many times have you used heroin (also called smack, junk, or China white)?" "During your life, how many times have you used methamphetamines (also called speed, crystal, crank, or ice)?" Or, "During your life, how many times have you taken steroid pills or shots without a doctor's prescription?"

^¶¶ Consumption of fruits and vegetables includes 100% fruit juice, fruit, green salad, potatoes (excluding French fries, fried potatoes, or potato chips), carrots, or other vegetables.

Alabama, Martha Holloway, Department of Education; Arkansas, Kathleen Courtney, M.S., Department of Education; Boston, Massachusetts, Nancy M. Strunk, M.S., Boston Public Schools; Chicago, Illinois, Margaret M. Finnegan, M.S., Chicago Public Schools; Colorado, Alyson Shupe, Ph.D., Department of Health; Dallas, Texas, Phyllis E. Simpson, Ph.D., M.S., Dallas Independent School District; Delaware, Janet Arns, M.S., Department of Education; Detroit, Michigan, Lisa Williams Brown, M.S., Detroit School District; District of Columbia, Linda S. Wright, M.A., District of Columbia Public Schools; Florida, Tammie M. Johnson, M.P.H., Department of Education; Ft. Lauderdale, Florida, Mike Weissberg, M.S., School Board of Broward County; Hawaii, Dan Yahata, Department of Education; Houston, Texas, Rose Haggarty, M.Ed., Houston Independent School District; Idaho, Barbara Eisenbarth, M.Ed., Department of Education; Illinois, Glenn Steinhausen, Ph.D., State Board of Education; Indiana, Sally J. Goss, M.S., Department of Health; Iowa, Sara A. Peterson, M.A., Department of Education; Kentucky, Julie Zlatos, M.S.S.W., Department of Education; Los Angeles, California, Rona Cole, Los Angeles Unified School District; Louisiana, Lillie Burns, M.A., Department of Education; Maine, Joni Foster, Department of Education; Massachusetts, Belinda Abbruzzese, M.P.H., Department of Education; Miami, Florida, LaShaun Polk, M.P.H., Miami-Dade County Public Schools; Michigan, Laurie Bechhofer, M.P.H., Department of Education; Milwaukee, Wisconsin, Sheryl Gotts, Milwaukee Public Schools; Mississippi, Pat Clemen, Department of Health; Missouri, Kevin Miller, M.A., Department of Elementary and Secondary Education; Montana, Susan Court, Office of Public Instruction; Nebraska, Cheryl Jappert, Department of Education; Nevada, Marianne Carr, M.A., Department of Education; New Hampshire, Ginny St. Martin, M.A.T., Department of Education; New Jersey, Sarah Kleinman, M.P.H., Department of Education; New Orleans, Louisiana, Stephanie M. Turlich, Orleans Parish School Board; New York, Jacquee Albers, M.S.E., Department of Education; New York City, New York, Mohamed N. Yasin, M.A., M.Ed., New York City Board of Education; North Carolina, Bradley McMillen, Ph.D., Department of Education; North Dakota, Linda L. Johnson, M.S., Department of Public Instruction; Orlando, Florida, Kathy Bowman, M.S., Orange County Public Schools; Palm Beach, Florida, Danette Fitzgerald, School District of Palm Beach County; Philadelphia, Pennsylvania, Bettyann Creighton, M.Ed., School District of Philadelphia; Rhode Island, Donald K. Perry, M.P.A., Department of Health; San Bernardino, California, Angela Jones, M.A., San Bernardino City Unified School District; San Diego, California, Margaret Kleinsmith, M.S., San Diego Unified School District; San Francisco, California, Phong Pham, M.A., San Francisco Unified School District; South Carolina, Lynn Hammond, Department of Education; South Dakota, Janet Ricketts, Department of Education and Cultural Affairs; Tennessee, Jerry Swaim, M.S., Department of Education; Texas, Philip Huang, M.D., M.P.H., Department of Health; Utah, Jacqueline Morasco, M.S., Office of Education; Vermont, Nancy Emberley, M.A.T., Department of Education; Wisconsin, Brian Weaver, Department of Public Instruction; Wyoming, Sunny Kaste, Department of Health.

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Youth Risk Behavior Surveillance --- United States, 2001

Introduction

Methods

Sampling National Youth Risk Behavior Survey

Data Collection

Results

Behaviors That Contribute to Unintentional Injuries Seat Belt Use

Behaviors That Contribute to Violence

Tobacco Use

Alcohol and Other Drug Use

Age of Initiation of Risk Behaviors

Tobacco, Alcohol, and Other Drug Use on School Property

Sexual Behaviors That Contribute to Unintended Pregnancy and STDs, Including HIV Infection

Dietary Behaviors

Physical Activity

Trends During 1991--2001

Discussion

Healthy People 2010

Limitations

Conclusion

Uses of YRBS Data

References

Sampling

National Youth Risk Behavior Survey

Behaviors That Contribute to Unintentional Injuries

Seat Belt Use