Data Types - Screening and Risk Factors Data Types

Direct Estimates are the usual estimates reported from a survey-directly estimated from the survey data using appropriate weighting. Most of these direct estimates are based on data from the Behavioral Risk Factor Surveillance System (BRFSS), a large annual telephone survey of U.S. households designed to measure at the state level.

State-Level or County-Level Modeled Estimates combine results from BRFSS and the National Health Interview Survey (NHIS), a smaller, in-person survey, using a statistical model that takes advantage of the strengths of each survey. These estimates:

For each outcome, the state level modeled estimates are controlled to the direct regional estimates and the county level modeled estimates are controlled to the controlled state level modeled estimates so the aggregated county level estimates equal to the corresponding state level estimates and the aggregated state level estimates equal to the corresponding regional level direct estimates.

See http://sae.cancer.govExternal Web Site Policy for more details.

Summary of Available Statistics by Data Type

  Direct Estimates Bias-Adjusted Modeled Estimates
Areas States
Time Period Most current single year Pooled years
Survey(s) BRFSS (or CPS or ANR*) BRFSS and NHIS combined
Topics Available Clinical Breast Exam
Fruit/Vegetable Servings
Home Blood Stool Test
Overweight or Obese
Pap Smear
Physical Activity
Signmoidoscopy or Colonoscopy
Smoking Not Allowed and Smoking Laws (not based on BRFSS*)
Fecal occult blood test (FOBT)
Sigmoidoscopy or Colonoscopy
FOBT or Sigmoidoscopy or Colonoscopy
Limitations Telephone-only survey method introduces bias and inaccuracies (greater for some statistics than for others) Depending on the local sample rate, estimates for small areas may not reflect local factors (such as a media campaign to promote mammograms)

* Smoking Not Allowed measures are direct estimates and are from the Current Population Survey (CPS) Tobacco Use Supplement. The data for Smoking Laws come from Americans for Nonsmokers' Rights (ANR) and are based on analysis of laws across the country.