How the Youth Risk Behavior Survey Works: The 2019 Methods

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This page summarizes the overview and methods report for the 2019 Youth Risk Behavior Survey, published by CDC in an MMWR Supplement.

Adolescence is usually a healthy time of life, but some high school students face risks that raise their chances of sexually transmitted disease (STD), including HIV, substance use, mental health problems, and violence or self-harm, and risky habits formed in adolescence often last into adulthood. In 2018 CDC reported that the leading causes of death among U.S. adolescents were motor-vehicle crashes, then suicide and homicide.

The Youth Risk Behavior Surveillance System (YRBSS), running since 1991, is the largest public health surveillance system in the United States. It tracks health behaviors, conditions and experiences of high school students in six areas:

behaviors that contribute to unintentional injury and violence;
tobacco use;
alcohol and other drug use;
sexual behaviors that contribute to unintended pregnancy and STD/HIV;
dietary behaviors;
physical inactivity.

It consists of a national Youth Risk Behavior Survey (YRBS) run by CDC and separate site-level surveys run by states, local school districts, territories and tribes.

Map of U.S. sites that conducted Youth Risk Behavior Surveys in 2019.

Sites with 2019 YRBS data: 44 states, 28 local school districts, three territories and two tribal governments had representative data. Figure: CDC.

The national survey

When: every other year, in the spring of odd-numbered years; the 2019 data were collected from August 2018 to June 2019.
Who: students in grades 9–12 at public and private schools in the 50 states and the District of Columbia. Alternative, special education, Department of Defense, Bureau of Indian Education and some vocational schools were left out, as were schools with 40 or fewer students in those grades.
How: an anonymous, voluntary, self-administered questionnaire on a computer-scannable booklet, taking one class period (about 45 minutes). Local parental permission procedures were followed, and CDC's Institutional Review Board approved the protocol.
Questions: 99 in 2019, the 89 of the standard questionnaire plus 10 national-only ones. All but height, weight and race were multiple choice with one answer. Questions are revised every cycle, cognitively tested, and have shown good test–retest reliability.

Sampling had three stages:

54 primary sampling units (counties, groups of small counties or parts of large ones) were drawn from 1,257, grouped into 16 strata by metropolitan status and by the share of Black and Hispanic students;
162 schools were drawn from those, plus 15 small schools for better coverage, 177 units covering 184 physical schools;
one or two classes per grade were drawn at random from a required subject or period, and all their students were eligible. Refusals were not replaced.

Response. Students completed 13,872 questionnaires in 136 schools; 195 failed quality checks, leaving 13,677. The school response rate was 75.1%, the student rate 80.3%, and the overall rate 60.3%.

Weighting by sex, race and ethnicity, and grade corrects for nonresponse and for oversampling of Black and Hispanic students, making the results nationally representative of students in grades 9–12. Analyses used SAS and SUDAAN; differences were judged significant at p<0.05, and long-term trends were tested with logistic regression, with Joinpoint used to find where nonlinear trends changed.

Who took part in 2019 (weighted)

Group	Share
Male	50.6%
Grade 9 / 10 / 11 / 12	26.6% / 25.5% / 24.2% / 23.5%
White / Hispanic / Black / other	51.2% / 26.1% / 12.2% / 10.6%
Heterosexual / gay or lesbian / bisexual / not sure	84.4% / 2.5% / 8.7% / 4.5%
No sexual contact	47.6%

Site-level surveys

States and districts survey public school students in grades 9–12 using the same methods, usually with two-stage cluster samples; some surveyed every school, and Vermont, the District of Columbia and Palau surveyed every student. Sites may add or drop questions but must use at least 60 of the 89 standard ones.

Until 2019, a site needed a 60% overall response rate for its data to be weighted. As response rates in federal surveys decline, CDC piloted nonresponse bias analyses in 2019 at three sites with rates of 50%–60% (Nebraska; Texas; and Spartanburg County, South Carolina) and found few significant differences, suggesting the data were generally representative.

In 2019 the median response rate was 65.0% for state surveys and 76.5% for district surveys.

Bar graph of the number of U.S. sites with representative YRBS data, 1991–2019.

Sites with representative YRBS data rose steadily after 1991, reaching 77 in 2019. Figure: CDC.

Scale and trends

Since 1991 the system has surveyed about 4.9 million students in about 2,100 separate surveys.
National overall response rates have stayed above 60%, peaking at 71% in 2009 and 2011 and holding in the low 60s in 2015–2019.
In 2019, 78 surveys including the national one had representative data, the most in the system's history. Site reports often go back to state and local agencies within 16 weeks.

Data from 1991–2019 are free to download, and can be explored in Youth Online and the newer YRBS Explorer. CDC is also updating reliability testing, piloting tablet-based surveys, and testing ways to break down results by school-level socioeconomic status and location; one study using that approach found students at schools in low socioeconomic areas more likely to experience violence, poor emotional well-being and suicidality.

Limitations

It covers only young people in school; about 5% of those aged 14–17 were not enrolled in 2019, and they may take more risks.
Over- or underreporting cannot be measured.
Not every state or district takes part or asks every standard question.
Cross-sectional data show association, not cause, and do not explain trends.
Questions on sexual and gender identity have limits; students may not yet know, or may misunderstand, the question.