• Component Description
• Eligible Sample
• Interview Setting and Mode of Administration
• Quality Assurance & Quality Control
• Data Processing and Editing
• Analytic Notes
• Codebook
  • SEQN - Respondent sequence number
  • DBQ010 - Ever breastfed or fed breastmilk
  • DBD030 - Age stopped breastfeeding(days)
  • DBD041 - Age first fed formula(days)
  • DBD050 - Age stopped receiving formula(days)
  • DBD055 - Age started other food/beverage
  • DBD061 - Age first fed milk(days)
  • DBQ073A - Type of milk first fed - whole milk
  • DBQ073B - Type of milk first fed - 2% milk
  • DBQ073C - Type of milk first fed - 1% milk
  • DBQ073D - Type of milk first fed - fat free milk
  • DBQ073E - Type of milk first fed - soy milk
  • DBQ073U - Type of milk first fed - other
  • DBD085 - CHECK ITEM
  • DBQ700 - How healthy is the diet
  • DBQ197 - Past 30 day milk product consumption
  • DBQ223A - You drink whole or regular milk
  • DBQ223B - You drink 2% fat milk
  • DBQ223C - You drink 1% fat milk
  • DBQ223D - You drink fat free/skim milk
  • DBQ223E - You drink soy milk
  • DBQ223U - You drink another type of milk
  • DBD225 - CHECK ITEM
  • DBQ229 - Regular milk use 5 times per week
  • DBQ235A - How often drank milk age 5-12
  • DBQ235B - How often drank milk age 13-17
  • DBQ235C - How often drank milk age 18-35
  • DBD265a - CHECK ITEM
  • DBQ301 - Community/Government meals delivered
  • DBQ330 - Eat meals at Community/Senior center
  • DBD355 - CHECK ITEM
  • DBQ360 - Attend kindergarten thru high school
  • DBQ370 - School serves school lunches
  • DBD381 - # of times/week get school lunch
  • DBQ390 - School lunch free, reduced or full price
  • DBQ400 - School serve complete breakfast each day
  • DBD411 - # of times/week get school breakfast
  • DBQ421 - School breakfast free/reduced/full price
  • DBQ422 - CHECK ITEM
  • DBQ424 - Summer program meal free/reduced price
  • DBD895 - # of meals not home prepared
  • DBD900 - # of meals from fast food or pizza place
  • DBD905 - # of ready-to-eat foods in past 30 days
  • DBD910 - # of frozen meals/pizza in past 30 days
  • DBQ715a - CHECK ITEM
  • CBQ596 - Heard of My Plate
  • CBQ606 - Looked up My Plate on internet
  • CBQ611 - Tried My Plate plan
  • DBQ930 - Main meal planner/preparer
  • DBQ935 - Shared meal planning/preparing duty
  • DBQ940 - Main food shopper
  • DBQ945 - Shared food shopping duty

National Health and Nutrition Examination Survey

2017-March 2020 Data Documentation, Codebook, and Frequencies

Diet Behavior & Nutrition (P_DBQ)

Data File: P_DBQ.xpt

First Published: October 2021

Last Revised: December 2021

Component Description

The NHANES program suspended field operations in March 2020 due to the coronavirus disease 2019 (COVID-19) pandemic. As a result, data collection for the NHANES 2019-2020 cycle was not completed and the collected data are not nationally representative. Therefore, data collected from 2019 to March 2020 were combined with data from the NHANES 2017-2018 cycle to form a nationally representative sample of NHANES 2017-March 2020 pre-pandemic data. These data are available to the public. Please refer to the Analytic Notes section for more details on the use of the data.

The Diet Behavior and Nutrition questionnaire (variable name prefix DBQ) provides personal interview data on various dietary behavior and nutrition related topics. Many of the questions were included in NHANES II (1976-80), Hispanic HANES (1982-84), NHANES III (1988-94), and NHANES 1999-2016. Topics included in the DBQ are:

• Breastfeeding and other childhood feeding practices (≤ 6 years);
• Current milk consumption pattern and types of milk (≥ 1 year);
• Milk consumption pattern throughout life span (≥ 20 years);
• Community or government meal program participation for seniors  (≥ 60 years);
• School meal program participation (4-19 years);
• Self-appraised healthfulness level of one’s own diet (≥ 16 years);
• Frequency of getting meals prepared away from home (≥ 1 year);
• Frequency of meals gotten from fast-food or pizza places (≥ 1 year);
• Use of convenience foods (≥ 1 year);
• Awareness of My Plate program (≥ 16 years); and
• Meal planner/shopper/preparer status (≥ 16 years).

Information on individual participant’s food choices, such as getting meals prepared away from home, meals from fast-food or pizza places, use of convenience foods or ready-to-eat meals bought in stores, and the participant’s awareness of the My Plate program as well as his/her meal planner/shopper/preparer status at home in the DBQ section were collected as part of the core set of the Flexible Consumer Behavior Survey (FCBS) module. The FCBS module has been included in NHANES since 2007, and was developed in collaboration with the Economic Research Service (ERS) of the U.S. Department of Agriculture (USDA). It is designed to collect information on people’s knowledge, attitudes, and beliefs toward nutrition and food choices. The FCBS module has two elements: a core set of questions asked during the NHANES household interview, and a supplementary module asked as a telephone follow-up interview with focuses specifically designed for each 2-year data collection cycle.

In addition to questions included in the DBQ section, the core set of questions for the FCBS module collected in the 2017-2018 and 2019-2020 survey cycles also included questions at the participant’s family level. For example, family monthly income and family assets, food expenditures, as well as the family’s participation on federal food assistance programs. The family food expenditures data are included in the Consumer Behavior (CBQ) section, while the monthly income and family assets data are included in the Income (INQ) section, and food program participation data are included in the Food Security (FSQ) section.

Data from the phone follow-up FCBS supplementary module are to be released in separate files and made available on the NHANES website as well. Similar to other datasets created from the NHANES 2017-March 2020 pre-pandemic sample, all FCBS related data files can be linked by the respondent sequence number (SEQN). For more information on the other FCBS related data, refer to the documentation accompanying the datasets.

Eligible Sample

All participants in the NHANES 2017-March 2020 pre-pandemic sample were eligible. The target age groups for individual questions in this section vary by the topic. For example, the questions pertaining to infant nutrition and breastfeeding were asked of proxy respondents for children 6 years of age and younger; and senior meal program participation questions were asked of respondents 60 years of age and older. Please review the questionnaire and codebook carefully. Frequency counts were verified during the preparation of the file.

Interview Setting and Mode of Administration

Questions on the frequencies of getting meals prepared away from home (DBD895), meals from fast-food or pizza places (DBD900), and use of convenience foods (DBD905 and DBD910) were answered by participants 12-15 years old, at the mobile examination center (MEC), using the Audio Computer Assisted Self-Interview (ACASI) system. The same questions were asked of participants 1-11 years and of participants 16 years and older, in the home, by trained interviewers using the Computer Assisted Personal Interview (CAPI) system. All other questions in this section were asked in the home, as well.

Hand cards showing response categories were also used for some questions. When necessary, the interviewers read the hand cards to respondents. Persons 16 years of age and older and emancipated minors were interviewed directly. A proxy provided information for survey participants who were under 16 years of age and for individuals who could not answer the questions themselves.

Quality Assurance & Quality Control

The CAPI system is programmed with built-in consistency checks to reduce data entry errors. CAPI also uses online help screens to assist interviewers in defining key terms used in the questionnaire. All data was reviewed by the NHANES field office staff for accuracy and completeness.

Data Processing and Editing

Frequency counts were checked, "skip" patterns were verified, and the reasonableness of question responses was reviewed. Edits were made to some variables to ensure the completeness, consistency, and analytic usefulness of the data. Edits were also made, when necessary, to address data disclosure concerns. When a variable was modified globally, as part of the editing process, the third letter in the variable name was changed from a Q (i.e., DBQ) to a D (i.e., DBD). For example, some data were collected using two variables (a number variable and a unit of measure variable) but combined into a single variable for data release purposes.

DBD020, DBD030, DBD041, DBD050, DBD055, and DBD061 (Breastfeeding and other childhood feeding practices)
This information was collected using two-part (number and unit) questions to allow respondents to report the age of interest in days, weeks, months, or years. The released variables were edited to standardize the reported age to number of days, using the following conversion factors: 7 days/week, 30.4 days/month and 365 days/year. If the age for the time stopped breastfeeding (DBD030), or stopped receiving formula (DBD050), or first fed milk (DBD060) was reported as older than 1095 days (3 years), the value was re-coded as "666666." Similarly, if the age for the time first fed formula (DBD041) was reported as older than 365 days (1 year), or the age for the time started other food/beverage than breastmilk/formula was reported as older than 730 days (2 years), the value was re-coded as "666666" as well.

DBD895 (Frequency of getting meals prepared away from home)
Respondents were asked how many times they had gotten meals that were prepared away from home in the past 7 days. If the frequency was reported as "never," the value was re-coded as "0." If the frequency was reported more than 21 times per week, the value was re-coded as "5555."

DBD900 (Frequency of getting meals from fast food or pizza places)
Respondents were asked how many times they had gotten meals from fast food or pizza places in the past 7 days. If the frequency was reported as "never," the value was re-coded as "0." If the frequency was reported more than 21 times per week, the value was re-coded as "5555."

DBD905 and DBD910 (Use of convenience foods)
This information was collected using two-part (number and unit) questions to allow respondents to report the frequency of interest as either per day, per week, or per month. The released variables were edited to standardize the reported frequency to number of times in the last 30 days. If the frequency was reported as "never," the value was re-coded as "0." If the frequency was reported more than 90 times in the last 30 days, the value was re-coded as "6666."

Analytic Notes

The COVID-19 pandemic required suspension of NHANES 2019-2020 field operations in March 2020 after data were collected in 18 of the 30 survey locations in the 2019-2020 sample. Data collection was cancelled for the remaining 12 locations. Because the collected data from 18 locations were not nationally representative, these data were combined with data from the previous cycle (2017-2018) to create a 2017-March 2020 pre-pandemic data file. A special weighting process was applied to the 2017-March 2020 pre-pandemic data file. The resulting sample weights in the present file should be used to calculate estimates from the combined cycles. These sample weights are not appropriate for independent analyses of the 2019-2020 data and will not yield nationally representative results for either the 2017-2018 data alone or the 2019-March 2020 data alone. Please refer to the NHANES website for additional information for the NHANES 2017-March 2020 pre-pandemic data, and for the previous 2017-2018 public use data file with specific weights for that 2-year cycle.

DBD895, DBD900, DBD905, and DBD910 (Frequency of getting meals prepared away from home, frequency of meals got from fast-food or pizza places, and use of convenience foods)
These questions were asked as part of household interview for participants 1-11 (proxy interview used) and 16 or more years of age, the interview sample weights may be used in their analysis. However, if the data is joined with other data from the Mobile Examination Center (MEC), the exam sample weights should be used. Analysis of these questions for participants 12-15 years old should use the exam sample weights because the questions were asked in the MEC for this age group.

Please refer to the NHANES Analytic Guidelines and the on-line NHANES Tutorial for further details on the use of sample weights and other analytic issues. Both are available on the NHANES website.

Codebook and Frequencies