Skip all navigation Skip to page navigation

DHHS Home | A-Z Site Map | Divisions | About Us | Contacts


Technical Notes 2016

Behavioral Risk Factor Surveillance System (BRFSS)

Detailed data tables for NC BRFSS survey items are posted by the SCHS on an annual basis. The exact wording for each question is used as a title for the majority of the web tables, however due to space limitations the titles may not include some introductory remarks and explanations for some questions. Although not all survey questions are presented in the web tables, the full questionnaire may be viewed online.

For the majority of survey items, the results are displayed by sex, race/ethnicity, age, education, and other socioeconomic variables. For the statewide and regional tables, disability status, veteran status and Hispanic origin are also displayed as demographic groups. Results are also posted separately by gender, by race (white and African American), and by selected risk factors (defined below).

Results for several sub-state regions are available in the NC Local Health Regions table-set. These include the North Carolina Association of Local Health Directors regions, Area Health Education Centers regions, and three broad regions of the state. A list of the counties in each regional grouping is shown at the end of this document.

The BRFSS Survey Methodology

The 2016 BRFSS Survey carries forward the new weighting and sampling methodology initiated in 2011. For a detailed description of the new methodology see the North Carolina BRFSS 2011 Annual Technical Notes.  In 2011, BRFSS results were based on a new weighting methodology that incorporates supplementary state population information (in addition to age, race, sex and ethnicity) by phone source (landline only, landline and cell, or cell-only), education level, marital status and renter/owner status. The effect of adding these new control variables to the weighting procedure helps reduce bias in BRFSS estimates and helps enhance the generalizability of the results to the statewide population.

In addition to changes in the weighting methodology, cell phone interviews were also added to the survey in 2011. The inclusion of cell phone interviews has helped to improve BRFSS coverage of young adults and Hispanics. In the 2016 North Carolina BRFSS Survey, there were 1,894 landline respondents and 4,643 cell phone respondents; their weighted percentages were 24.9 percent and 75.1 percent, respectively.

Interpreting Results

For several years the CDC BRFSS program has suppressed prevalence estimates which did not meet minimal criteria for statistical reliability based on sample size and the width of the confidence intervals. To better meet our goal of providing high quality health information for better informed decisions and effective health policies, the SCHS has adopted this practice for our BRFSS web tables.

In our 2016 tables, we suppress prevalence estimates when any of the following criteria are met:

  1. There are fewer than 10 respondents in the numerator (i.e. the number of respondents associated with the response categories, e.g. “Yes-No”).
  2. There are fewer than 50 respondents in the denominator (i.e. the total number of respondents to a question).
  3. The width of the confidence interval for the prevalence estimate is greater than 20.
  4. Cases where a table cell estimate has a relative standard error of greater than 30 percent. The relative standard error is a measure of a statistical estimate's reliability obtained by dividing the standard error by the estimate; then multiplied by 100 to be expressed as a percentage.

Some topics are age-dependent topics, such as prostate cancer screening, which was asked only of men 40 years or older. Please note age varies for particular survey items in the web table’s footnotes or as cited in the table title.

Weighted BRFSS data are used in all calculations, so percentages shown in web tables cannot be derived exactly from the numbers presented. BRFSS data are weighted for the probability of selection of a telephone number, the number of adults in a household, and the number of phones in a household and adjusted to reflect the demographic distribution of North Carolina's adult population (ages 18 and older).

Respondents who refused to answer or did not know the answer were excluded from most calculations in these tables. However, there are instances when "Don't know/Not sure" responses may provide valuable information and are included in the response categories.

For additional technical information about BRFSS, please visit the national BRFSS web site.

Risk Factors and Calculated Variables Presented in the 2016 BRFSS Results

Body Mass Index Grouping

Body mass index (BMI) is computed as weight in kilograms divided by height in meters squared:(kg/ m2). BMI is an intermediate variable used in calculating these measures:
Underweight: BMI less than 18.5, Recommended Range: BMI 18.5 to 24.9, Overweight: BMI 25.0 to 29.9, Obese: BMI greater than 29.9. and Overweight or Obese: BMI greater than 24.9.

Health Insurance Coverage - Age Under 65

Yes: All respondents less than age 65 who answered YES to the Core question on having any kind of health (HLTHPLN1). Respondents with missing age were excluded.
No: All respondents less than age 65 who answered NO to the Core question on having any kind of health (HLTHPLN1). Respondents with missing age were excluded.

Health Insurance Coverage for Those Employed for Wages (Age under 65)

Yes: All respondents less than age 65 who answered YES to the Core question on having any kind of health (HLTHPLN1), and answered “yes” to being employed for wages. Respondents with missing age were excluded.
No: All respondents less than age 65 who answered YES to the Core question on having any kind of health (HLTHPLN1), and answered something OTHER then “yes” to being employed for wages. Respondents with missing age were excluded.

Smoking Status

Current Smoker (every day): Respondents who have smoked at least 100 cigarettes in their lifetime and now smoke every day.
Current Smoker (some days): Respondents who have smoked at least 100 cigarettes in their lifetime and now smoke some days.
Former Smoker: Respondents who have smoked at least 100 cigarettes in their lifetime and currently do not smoke.
Never Smoked: Respondents who have not smoked at least 100 cigarettes in their lifetime.

Current Smoker

Yes: Current Smoker (every day or some days)
No: Former Smoker or Never Smoked.

Binge Drinking

No : Respondents who report they did not drink in the past 30 days, or who drank in the past 30 days but did not have five or more drinks for males or four or more drinks for females on an occasion.
Yes : Respondents who report they did drink in the past 30 days and had five or more drinks for males or four or more drinks for females on one or more occasions in the past month.

Heavy Drinking

Yes: Respondents reported having MORE than 2 drinks/day for MALES and MORE than 1 drink/day for FEMALES.
No: Respondents reported having LESS than or equal to 2 drinks/day for MALES and LESS than or equal to 1 drink/day for FEMALES.

Disability Status and Functional Disability

Disability status is based on the two questions in CDC Optional Module 25. Respondents who answered “yes” to either question are considered to have a disability; those who answered “no” to both questions have no disability. These questions have been used to define disability status since 2011.

Beginning with the 2016 survey, the BRFSS includes all six questions recommended by the U.S. Department of Health and Human Services as the national standard for identifying disabilities in population-based health surveys.i The questions (8.22 through 8.27) ask whether the respondent has serious difficulty with several domains of functioning. Respondents who answered “yes” to at least one of these questions is defined as having a functional disability. Those who answered “no” to all six questions have no functional disability.

Beginning in 2017, functional disability will replace disability status on the BRFSS. We included both measures on the 2016 survey so that their impact on indicators of interest could be compared. Please contact the BRFSS Staff if you have questions about this change.

Rural-Urban Resident

Respondent’s county of residence is coded as rural, suburban or urban counties based on the North Carolina Rural Center’s county classification. For 2016, Forsyth, Guilford, Mecklenburg, and Wake were classified as urban counties. Alamance, Buncombe, Cabarrus, Catawba, Cumberland, Davidson, Gaston, Henderson, Iredell, Lincoln, Orange, Pitt, Rowan, and Union were classified as suburban or regional city counties. The remaining counties are classified as rural.

Poverty Level

This is a rough measure of how the respondent’s household income compares to the 2016 poverty guidelines established by the U.S. Department of Health and Human Services. The respondent’s income (the mean of the income category they choose in question 8.17) is divided by the poverty level income for their household size, then converted to a percentage. The result expresses the respondent’s household income as a percentage of poverty income. In 2016, poverty level income for a single-person household was $11,770. A respondent living alone whose income was $11,770 would be at “100% poverty.” If their income was $23,540, they would be at “200% poverty.” This continuous poverty level variable is categorized for reporting.

Please contact the BRFSS Staff if you have questions about this measure or would like a copy of the SAS code used to create the variable.

North Carolina Department of Commerce County Tier

Respondent’s county of residence is coded into of the N.C. Department of Commerce 2016 County Tier Designations. The tiers measure economic well-being based on unemployment, median household income, population growth, and property tax base.

Family Planning Calculated Variables

Several variables relating to family planning practices are derived from questions 2, 3, and 4 in North Carolina Module 6, Preconception Health. These questions were only asked of women aged 18 to 44.

Women at Risk for Unintended Pregnancy. Women who are sexually active with a male partner, not pregnant or trying to get pregnant, and capable of becoming pregnant in the absence of using contraception are considered to be at risk. The remaining women are coded as not at risk.

Women in Need of Contraceptive Services. This variable is very similar to “at risk for unintended pregnancy.” It excludes women who have chosen surgical sterilization as a means of contraception.

Effectiveness of Current Contraceptive Method. This variable classifies the contraceptive method identified in questions 3 and 4 as highly, moderately, or least effective as described below.

  • Highly effective methods include male or female sterilization, contraceptive implants, or IUDs.
  • Moderately effective methods include shots such as Depo-Provera, birth control pills, contraceptive patches, contraceptive rings, or diaphragms.
  • Least effective methods include condoms, rhythm method, withdrawal, contraceptive foams, jelly or creams, cervical cap, sponges, or emergency contraception (morning after pill).

Respondents who were sexually active with a male partner and capable of getting pregnant but used none of the above contraceptive methods were codes as using no contraceptive method.

Used Long-Acting Reversible Contraceptive (LARC) Method. Respondents who were sexually active with a male partner, capable of getting pregnant who used a contraceptive implant or IUD are coded as “Yes, used a LARC.” Those using any other contraceptive method are coded as not using a LARC.

Please contact the BRFSS Staff if you have questions about these measures or would like a copy of the SAS code used to create them.

Strengths and Limitations of the BRFSS Survey Data

One limitation of a telephone survey is the lack of coverage of persons who live in households without a telephone. Households without a telephone are, on average, of lower income. Therefore, the results might understate the true level of health risk in the total population of adults in North Carolina. A second limitation is due to the fact that the data are self-reported by the respondents. Respondents might underreport health risk behaviors, especially those that are illegal or socially unacceptable. A third limitation is that these data are cross-sectional, collected in a single point in time. As a result, causality cannot be inferred from BRFSS survey results. All that can be determined is the likelihood of an association of between two or more variables, such as the association between smoking and cardiovascular disease – these results do not permit one to say that smoking “causes” heart disease.

Non-response is another limitation. Non-response to telephone and paper surveys has become an increasing problem for public health surveillance. In 2015, North Carolina’s non-response rate was 57.1 percent.ii iii This means that out of all eligible survey participants, we "lost" almost 57 percent due to non-response. Non-responders may answer questions differently than responders. As a result, non-response poses a potential threat to the validity of the survey. Readers should carefully consider the non-response rates when assessing the results from any survey.

There are some significant advantages of the telephone survey methodology, including better quality control over data collection made possible by a computer-assisted-telephone-interviewing system, relatively low cost, and speed of data collection. The BRFSS methodology has been used and evaluated by the CDC and participating states since 1984. The content of the survey questions, questionnaire design, data collection procedures, interviewing techniques, and editing procedures have been carefully developed to improve data quality and reduce the potential for bias.

Definition of Regions

North Carolina Association of Local Health Directors Regions

Region 1 & 2: Avery, Buncombe, Burke, Caldwell, Cherokee, Clay, Cleveland, Graham, Haywood, Henderson, Jackson, Macon, Madison, McDowell, Mitchell, Polk, Rutherford, Swain, Transylvania, Yancey counties.

Region 3: Alleghany, Ashe, Davidson, Davie, Forsyth, Stokes, Surry, Watauga, Wilkes, Yadkin counties.

Region 4: Alexander, Cabarrus, Catawba, Gaston, Iredell, Lincoln, Mecklenburg, Rowan, Stanly, Union counties.

Region 5: Alamance, Caswell, Chatham, Durham, Guilford, Orange, Person, Randolph, Rockingham counties.

Region 6: Anson, Cumberland, Harnett, Hoke, Lee, Montgomery, Moore, Richmond, Scotland counties.

Region 7: Edgecombe, Franklin, Granville, Halifax, Johnston, Nash, Wake, Vance, Warren, Wilson counties.

Region 8: Bladen, Brunswick, Columbus, Duplin, New Hanover, Onslow, Pender, Robeson, Sampson counties.

Region 9: Bertie, Camden, Chowan, Currituck, Dare, Gates, Hertford, Hyde, Martin, Northhampton, Pasquotank, Perquimans, Tyrell, Washington, counties.

Region 10: Beaufort, Carteret, Craven, Greene, Jones, Lenoir, Pamlico, Pitt, Wayne counties.

State Regions

Eastern NC: Beaufort, Bertie, Bladen, Brunswick, Camden, Carteret, Chowan, Columbus, Craven, Cumberland, Currituck, Dare, Duplin, Edgecombe, Gates, Greene, Halifax, Harnett, Hertford, Hoke, Hyde, Johnston, Jones, Lenoir, Martin, Nash, New Hanover, Northampton, Onslow, Pamlico, Pasquotank, Pender, Perquimans, Pitt, Robeson, Sampson, Scotland, Tyrrell, Washington, Wayne, and Wilson counties

Piedmont: Alamance, Alexander, Anson, Cabarrus, Caswell, Catawba, Chatham, Cleveland, Davidson, Davie, Durham, Forsyth, Franklin, Gaston, Granville, Guilford, Iredell, Lee, Lincoln, Mecklenburg, Montgomery, Moore, Orange, Person, Randolph, Richmond, Rockingham, Rowan, Stanly, Stokes, Union, Vance, Wake, Warren, and Yadkin counties.

Western NC: Alleghany, Ashe, Avery, Buncombe, Burke, Caldwell, Cherokee, Clay, Graham, Haywood, Henderson, Jackson, McDowell, Macon, Madison, Mitchell, Polk, Rutherford, Surry, Swain, Transylvania, Watauga, Wilkes, and Yancey counties.

Area Health Education Centers (AHEC)

Mountain AHEC: Buncombe, Cherokee, Clay, Graham, Haywood, Henderson, Jackson, Macon, Madison, McDowell, Mitchell, Polk, Rutherford, Swain, Transylvania, Yancey counties.

Northwest: Alexander, Alleghany, Ashe, Avery, Burke, Caldwell, Catawba, Davidson, Davie, Forsyth, Iredell, Rowan, Stokes, Surry, Watauga, Wilkes, Yadkin counties.

Charlotte: Anson, Cabarrus, Cleveland, Gaston, Lincoln, Mecklenburg, Stanly, Union counties.

Greensboro: Alamance, Caswell, Chatham, Guilford, Montgomery, Orange, Randolph, Rockingham counties.

Southern Regional: Bladen, Cumberland, Harnett, Hoke, Moore, Richmond, Robeson, Sampson, Scotland counties.

Southeast: Brunswick, Columbus, Duplin, Pender, New Hanover counties.

Wake: Durham, Franklin, Granville, Johnston, Lee, Person, Vance, Wake, Warren counties.

Area L & Eastern: Beaufort, Bertie, Camden, Carteret, Chowan, Craven, Currituck, Dare, Edgecombe, Gates, Greene, Halifax, Hertford, Hyde, Jones, Lenoir, Martin, Nash, Northampton, Onslow, Pamlico, Pasquotank, Perquimans, Pitt, Tyrrell, Washington, Wayne, Wilson counties.


iBased on section 4302 of the Affordable Care Act, the Department of Health and Human Services issued data collection standard guidance to include a standard set of disability identifiers in all national population health surveys (

iiResponse rates for the BRFSS are calculated using standards set by the American Association of Public Opinion Research (AAPOR) Response Rate Formula #4 (

iiiThe CDC had not published our 2016 response rate at the time these tables were posted. We will revise this document to include the 2016 rates when they become available.

Return to 2016 BRFSS Annual Results Table of Contents