1.3 Valid and Reliable Health Data Sources and Databases
Key Takeaways
- The Youth Risk Behavior Surveillance System (YRBSS) is the CDC's biennial survey of six categories of priority health-risk behaviors among 9th-12th graders, making it the single most cited source for school health needs data.
- Source credibility for the Praxis 5857 is judged by sponsor, peer review, currency, and freedom from commercial interest -- a government (.gov), university (.edu), or professional association (.org) sponsor with a named author and a review date outranks a commercial (.com) page selling a product.
- CDC surveillance systems differ by population: YRBSS surveys adolescents, BRFSS surveys adults by telephone, NHANES combines interviews with physical examinations and lab work, and the School Health Profiles surveys school policies and practices.
- Peer-reviewed journals such as the Journal of School Health and the Journal of Adolescent Health represent the highest tier of evidence because independent experts screened the methods before publication.
- SHAPE America, the American Medical Association (AMA), the National Institutes of Health (NIH), and the World Health Organization (WHO) are the professional and international bodies the ETS blueprint names explicitly alongside YRBSS and CDC.
Why the Exam Tests Data Sources by Name
Content Category I lists "valid and reliable data sources and databases (e.g., YRBSS, NIH, CDC, SHAPE America, AMA, WHO, and peer-reviewed journals)" as its own topic, separate from the research-methods topic. That separation matters. Research methods ask how data were collected; this topic asks which source you should reach for and why you should trust it. Exam items typically present a teacher who needs a specific number -- the percentage of local high schoolers who vape, national adult obesity trends, a nutrient reference value -- and ask which database supplies it.
A valid source measures what it claims to measure. A reliable source produces consistent results when the measurement is repeated. A source can be reliable but not valid: a poorly worded question asked identically every two years produces stable, consistently wrong numbers.
The Major Federal Surveillance Systems
| System | Sponsor | Population | Method | Cycle | What it answers |
|---|---|---|---|---|---|
| YRBSS (Youth Risk Behavior Surveillance System) | CDC | Students in grades 9-12 (national, state, and large urban district samples) | Anonymous self-report questionnaire in classrooms | Every 2 years (odd years) | "What percentage of high school students report current tobacco, alcohol, or sexual risk behavior?" |
| BRFSS (Behavioral Risk Factor Surveillance System) | CDC + states | Adults 18+ | Telephone interview | Continuous, annual estimates | "What share of adults in my state are physically inactive?" |
| NHANES (National Health and Nutrition Examination Survey) | CDC / NCHS | All ages | Interview plus physical exam and laboratory testing in a mobile exam center | Continuous, 2-year data releases | "What is the measured -- not self-reported -- prevalence of obesity or vitamin D deficiency?" |
| School Health Profiles | CDC | School principals and lead health teachers | Mail/online survey of schools | Every 2 years (even years) | "Do schools require health education, and what topics do they cover?" |
| NSCH (National Survey of Children's Health) | HRSA | Children 0-17, parent-reported | Household survey | Annual | "How many children have a medical home or unmet mental health need?" |
The distinction the exam loves
YRBSS and BRFSS are self-report. NHANES is measured. When an item asks which source gives the most accurate national obesity prevalence, the answer is NHANES, because height and weight are measured by trained technicians rather than reported by the respondent. Self-report systematically understates weight and overstates height.
When an item asks about adolescent risk behaviors specifically, the answer is YRBSS. The six YRBSS priority categories are worth memorizing:
- Behaviors contributing to unintentional injuries and violence
- Tobacco use
- Alcohol and other drug use
- Sexual behaviors related to unintended pregnancy and sexually transmitted infections
- Unhealthy dietary behaviors
- Physical inactivity
Professional, Governmental, and International Bodies
- CDC (Centers for Disease Control and Prevention) -- U.S. surveillance, outbreak data, immunization schedules, the Health Education Curriculum Analysis Tool (HECAT), and the Whole School, Whole Community, Whole Child framework.
- NIH (National Institutes of Health) -- the federal biomedical research funder; its institutes (NCI, NIAAA, NIDA, NHLBI) publish research syntheses and MedlinePlus consumer material through the National Library of Medicine.
- WHO (World Health Organization) -- global health statistics, international disease classification, and pandemic guidance. Reach for WHO when the question is international in scope.
- AMA (American Medical Association) -- physician professional association; publishes JAMA and clinical policy positions.
- SHAPE America (Society of Health and Physical Educators) -- the professional body whose teaching standards ETS used to build the 5857 test. Publishes the National Health Education Standards, the National Physical Education Standards, position statements, and the Journal of Physical Education, Recreation & Dance.
- ODPHP / health.gov -- issues the Physical Activity Guidelines for Americans and, jointly with USDA, the Dietary Guidelines for Americans.
Applying Credibility Criteria
Standard 3 of the National Health Education Standards makes accessing valid information a student skill, so the exam expects you to teach a screening routine, not just use one. A durable classroom heuristic:
| Criterion | Question students ask | Red flag |
|---|---|---|
| Sponsor | Who paid for and hosts this page? | The sponsor sells the product being recommended |
| Author | Is a named person with relevant credentials responsible? | No byline, or credentials that do not match the topic |
| Currency | When was this reviewed or updated? | No date, or a date more than a few years old for fast-moving topics |
| Evidence | Are claims linked to primary research or official data? | Testimonials and anecdotes instead of citations |
| Purpose | Is the goal to inform, or to sell, or to persuade politically? | Urgency language, "doctors don't want you to know," one-sided framing |
Domain suffixes are a starting point, not a verdict. A .gov page is usually authoritative and a .com page is usually commercial, but reputable hospital systems and journals use .org and .com addresses, and a .edu address can host an unreviewed student project. Teach students to check sponsor and evidence rather than stopping at the suffix.
Classroom Application
A health teacher planning a vaping unit works down a source ladder:
- Local YRBSS data (state or large-district file) to establish how many of these students vape -- this is what makes the unit relevant.
- National YRBSS for trend context over the last decade.
- CDC and NIDA for the physiological and addiction content.
- Peer-reviewed journals (Journal of Adolescent Health, Tobacco Control) for the effectiveness evidence behind the prevention strategy chosen.
- A commercial vape-industry site used only as an artifact for a media-literacy analysis -- never as a content source.
Common Praxis Traps
- Trap 1: Choosing BRFSS for a school question. BRFSS surveys adults. If the stem names students, the answer is YRBSS.
- Trap 2: Treating self-report as measurement. If a stem stresses accuracy of body composition or biomarkers, the answer is NHANES.
- Trap 3: Ranking a professional association above peer review. Association position statements are credible, but when a stem contrasts "an organization's website" with "a peer-reviewed study," peer review is the stronger evidence tier.
- Trap 4: Judging by domain suffix alone. Distractors that say "any .org site is trustworthy" are wrong; .org is available to advocacy groups of every quality.
A high school health teacher wants the most accurate national estimate of measured obesity prevalence among adolescents, not students' own descriptions of their weight. Which data source should the teacher use?
Which of the following is NOT one of the six categories of priority health-risk behaviors monitored by the YRBSS?
Students evaluating a website about a weight-loss supplement find no author listed, no publication date, testimonials instead of research citations, and an online store selling the supplement. Which credibility criterion is MOST directly violated by the online store?
A district health coordinator needs to know what percentage of schools in the state require health education and which topics those courses cover. Which CDC data source is designed to answer this question?