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See Software for Analysis of YRBS Data [pdf 285K] for a review of software packages suitable for analyzing YRBS data and guidance on how to use them.
National, state, territory, and local YRBS data come from separate scientific samples of schools and students. National YRBS data are not the aggregate of the state YRBS data. State, territory, and local YRBS data are not subsets of the National YRBS data set. National, state, territory, and local YRBS’s all follow the same survey methodology and use the same core questionnaire.
No. The national YRBS sample is designed to be representative of students in grades 9-12 in the United States overall and therefore does not necessarily include students from every state.
See 2007 National Data Files and Documentation and 1991-2005 National Data Files and Documentation.
Results are not available from every state because some states do not participate in the YRBS (in 2007, California, Louisiana, Minnesota, Pennsylvania, Virginia, and Washington did not participate) and some states that do participate did not achieve a high enough overall response rate to receive weighted results (in 2007, Alabama, New Jersey, Nebraska, Colorado, and Oregon did participate but did not get weighted data); therefore, their results are not posted on this Web site. The 2007 YRBS Participation Map and the YRBS History of Participation & Data Quality tables provide more details on which states have conducted a YRBS and whether they obtained weighted data.
In 2007, CDC funded 22 large urban school districts to conduct a YRBS. Six of them (Miami-Dade County, FL; Broward County, FL; DeKalb County, GA; Orange County, FL; Hillsborough County, FL; and Charlotte-Mecklenburg County, NC) are county-based school districts. The other funded school districts are identified on the YRBS Participation Map and the YRBS History of Participation & Data Quality tables. County level identifiers are not available on the National YRBS data file or on state data files.
State and local data files and documentation are owned and controlled by the jurisdictions that conducted the survey. Many states and districts have given CDC permission to distribute their data files upon request. Other states and districts manage the distribution of their data files themselves. For information on acquiring data files from specific states or districts, please contact us using this form.
The SAS format library contains the formats used to make SAS output more readable. Formats are linked to the data so that results are displayed as words (“Male” or “Female”, for instance) instead of numbers (1 or 2). The SAS YRBS data file is designed to use its companion format library. You should download both the data file and the format library if you want to use SAS to analyze YRBS data.
The following example SAS program shows how to use the format library. It assumes that both the data file and the format library have been downloaded to “c:\data”. Note that the program contains two libname statements. The first libname statement indicates where the data file is located; the second libname statement indicates where the format library is located.
libname mydata 'c:\data'; /* tells SAS where the data are */
libname library 'c:\data'; /* tells SAS where the formats are */proc freq data=mydata.yrbs2005;
tables q2;
run;Using the format library is recommended but technically is optional. If you do not want to use the format library, include the following statement at the start of your SAS program:
options nofmterr; /* tells SAS to not look for formats */
Please note that each year of YRBS data has its own format library. Format libraries are not the same across years of data.
For further information on using format libraries, please consult your SAS documentation.
State, territorial, and local agencies and nongovernmental organizations use YRBS data to set and track progress toward meeting school health and health promotion program goals, support modification of school health curricula or other programs, support new legislation and policies that promote health, and seek funding and other support for new initiatives.
CDC and other federal agencies routinely use YRBS data to assess trends in priority health risk behaviors among high school students, monitor progress toward achieving 15 Healthy People 2010 objectives and 3 leading health indicators, and evaluate the contribution of broad prevention efforts in schools and other settings toward helping the nation reduce health risk behaviors among youth.
Yes. The YRBSS tracks aggregate changes in student behavior over time. See the YRBS Trend Fact Sheets for more information.
No. Each year a new sample of schools and students is drawn. Students who participated cannot be tracked because no identifying information is collected.
Although prevalence estimates generated for students in each racial/ethnic subgroup are representative of these students nationally, caution should be used when analyzing and interpreting these data. Because of the small numbers of students in some racial/ethnic subgroups who participate in any single National YRBS, the estimates will lack precision. Precision can be improved by combining multiple years of National YRBS data.
The YRBS questionnaire should be cited as follows:
Centers for Disease Control and Prevention. 2007 Youth Risk Behavior Survey. Available at: www.cdc.gov/yrbss. Accessed on [date].
The YRBSS assesses six categories of priority health risk behaviors—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 HIV infection; unhealthy dietary behaviors; and physical inactivity—plus overweight and asthma.
There is no evidence that simply asking students about health risk behaviors will encourage them to try that behavior.
Yes. State and local agencies that conduct a YRBS can add or delete questions to meet their policy or programmatic needs. Specific guidance on the parameters that must be followed during questionnaire modification is provided to those agencies funded by CDC to conduct a YRBS.
One class period is needed. It takes approximately 10 minutes for the survey administrator to distribute survey materials and read directions to the students. It then takes approximately 35 minutes for students to record their responses. No physical test or exam is involved.
YRBS procedures are designed to protect student privacy by allowing for anonymous participation. Participation in the YRBS is voluntary. Local parental permission procedures are followed. Students complete the self-administered questionnaire during one class period and record their responses on a computer-scannable questionnaire booklet or separate answer sheet.
Yes. Local parental permission procedures are followed prior to administration of a YRBS.
No. The YRBS is always a voluntary activity for states, school districts, schools, and students.
Not in a YRBS supported by CDC. Any district or school may choose to conduct its own YRBS. See A Guide to Conducting Your Own Youth Risk Behavior Survey [pdf 108K] for information useful to communities and groups that plan to conduct their own YRBS survey.
Research indicates data of this nature may be gathered as credibly from adolescents as from adults. Internal reliability checks help identify the small percentage of students who falsify their answers. To obtain truthful answers, students must perceive the survey as important and know procedures have been developed to protect their privacy and allow for anonymous participation.
The Methodology of the Youth Risk Behavior Surveillance System [pdf 270K] contains a description of most of the methodological studies conducted to date on the YRBS questionnaire or YRBS data collection procedures. In addition, the list of YRBS reports and publications contains the actual journal articles describing the results of these studies.
These methodological studies include test-retest reliability studies on the 1991 and 1999 versions of the questionnaire; a study assessing the validity of self-reported height and weight; a study assessing the effect of changing the race/ethnicity question; a study examining how varying honesty appeals, question wording, and data-editing protocols affect prevalence estimates; and a study examining how varying the mode and setting of survey administration affects prevalence estimates.
Weighting is a mathematical procedure that makes data representative of the population from which it was drawn. In the YRBSS, only surveys with a scientifically drawn sample, appropriate documentation, and an overall response rate of at least 60% are weighted.
YRBS data are weighted to adjust for school and student nonresponse and to make the data representative of the population of students from which the sample was drawn. Generally, these adjustments are made by applying a weight based on student sex, grade, and race/ethnicity.
National YRBS data are representative of all public and private school students in grades 9-12 in the 50 states and the District of Columbia. National YRBS data are not the aggregate of the state YRBS data; the National YRBS uses a separate scientific sample of schools and students.
State, territory and local YRBS data that are weighted are representative of all public school students in grades 9-12 in the respective jurisdiction. State, territory, and local YRBS data that are not weighted are representative only of the students who completed the survey in the respective jurisdiction.
For the national, state, territory, and local YRBS samples, schools are selected with probability proportional to the size of student enrollment in grades 9-12 and then required classes of students (e.g., English classes) are randomly selected to participate. Within selected classes, all students are eligible to participate. See the Methodology of the Youth Risk Behavior Surveillance System [pdf 270K] for a more detailed description of sampling procedures.
See A Guide to Conducting Your Own Youth Risk Behavior Survey [pdf 108K] for information useful to communities and groups that plan to conduct their own YRBS survey.
The YRBS questionnaire is in the public domain and no permission is required to use it. You may download the questionnaire no charge. See Questionnaires and Item Rationale for the most recent YRBS questionnaires.
CDC provides data processing assistance only to states, territories, and large urban school districts that it funds directly to conduct a YRBS. However, information on how the data are processed can be found on the YRBS National Data Files and Documentation page and in the Methodology of the Youth Risk Behavior Surveillance System [pdf 270K].
CDC has funding available for all 50 state education agencies and only a small number of territories, tribal governments, and large urban school districts during each five year funding cycle.
Documents on this page are available in Portable Document Format (PDF). Learn more about viewing and printing these documents with Acrobat Reader.
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