Component Description
The Diet Behavior and Nutrition (variable name prefix DBQ) section 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 1999-2008. Topics included in the section are:
- Breastfeeding and other childhood feeding practices (<= 6 yr)
- Current milk consumption pattern and types of milk (>= 1 yr)
- Milk consumption pattern throughout the life span (>= 20 yr)
- Community or government meal program participation (>= 60 yr)
- School meal program participation (4-19 yr)
- Self-appraised healthfulness level of one’s own diet (>= 16 yr)
- Frequency of getting meals prepared away from home (>= 1 yr)
- Frequency of meals got from fast-food or pizza places (>= 1 yr)
- Use of convenience foods (>= 1 yr)
- Self-perceived vegetarian (>= 1 yr)
- Food allergy (>= 1 yr)
- Meal planner/shopper/preparer status (>= 16 yr)
Starting 2009, breastfeeding related questions in the DBQ section were revised based on the 2006 National Immunization Survey (NIS). These revised questions have been through extensive cognitive testing conducted by NIS in 2004-2005. Most current CDC recommendations discourage introducing any milk other than breast milk or iron-fortified infant formula to infant less than 12 month old. The revised breastfeeding questions are more specific in capturing the first introduction of anything other than breast milk. Therefore, they will improve the validity of the measure of excusive breastfeeding. Please refer to the CDC breastfeeding website for more information on NIS breastfeeding questions: http://www.cdc.gov/breastfeeding/data/NIS_data/survey_methods.htm
In addition,“Soy milk” was added to the response categories for type of milk questions (i.e., DBQ073 and DBQ223) to reflect the current market and consumer behaviors.
Changes to the breastfeeding related questions
| 2007-2008 |
2009-2010 |
| DBD010: Was {SP} ever breastfed or fed breastmilk? |
Same as 2007-2008 |
| DBD020: How old was {SP} when {he/she} was first fed something other than breastmilk or water? |
Replaced with DBD055 (see below) |
| DBD030: How old was {SP} when {he/she} completely stopped breastfeeding or being fed breastmilk? |
Same as 2007-2008 |
| DBD040: How old was {SP} when {he/she} was first fed formula on a daily basis? |
Renamed as DBD041 with the phrase “on a daily basis” deleted |
| DBD050: How old was {SP} when {he/she} completely stopped drinking formula? |
Same as 2007-2008 |
| DBD055 is a new question in 2009-2010. |
DBD055: This next question is about the first thing that {SP} was given other than breast milk or formula. Please include juice, cow’s milk, sugar water, baby food, or anything else that {SP} might have been given, even water. How old was {SP} when {he/she} was first fed anything other than breast milk or formula? |
| DBD060: How old was {SP} when {he/she} was first fed milk on a daily basis? |
Renamed as DBD061 with the phrase “on a daily basis” deleted |
| DBQ072: What type of milk was {SP} first fed on a daily basis? Was it whole or regular, 2% fat or reduced-fat milk, 1% fat or low-fat milk (includes 0.5% fat milk or “low-fat milk” not further specified), fat-free, skim or nonfat milk, or an other type? |
Renamed as DBQ073 with a new response category, “soy milk”, added |
| DBD080: How old was {SP} when {he/she} started eating solid foods [such as strained foods like baby food or any other non-liquid foods] on a daily basis? |
Replaced with DBD055 (see above) |
The Flexible Consumer Behavior Survey (FCBS) module was first added to the NHANES in 2007. This module 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 in the household interview, and a supplementary module asked in a telephone follow-up interview with focuses specifically designed for each 2-year data collection cycle.
The core set of the FCBS module collects information on individual participant’s food choices, such as getting meals prepared away from home, meals got from fast-food or pizza places, use of convenience foods or ready-to-eat meals bought in stores, and participant’s self-perceived vegetarian status, food allergy, and meal planner/shopper/preparer status at home. These data are included as part of the present DBQ section.
The core set of the FCBS module also includes questions at participant’s family level. For example, family member’s use of special diet, availability of certain type of foods in the family, food expenditures, as well as time spent on food shopping and cooking dinner, and meals eaten together in the family. These family level questions, in the core set of the FCBS module, are included in the Consumer Behavior (CBQ) section and will be released in a separate file.
Data from the phone follow-up FCBS supplementary module will also be released in separate files and made available on the NHANES website. Similar to other datasets in the NHANES 2009-2010 release cycle, all FCBS related data files can be linked by the respondent sequence number (SEQN). The complete 2009-2010 FCBS questionnaire is available at the NHANES website. For more information on the other FCBS related data, refer to the documentations accompanying the datasets.
Eligible Sample
The target age groups for questions in this section vary by the topic. For example, the questions pertaining to infant nutrition and breast-feeding 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 got from fast-food or pizza places (DBD900), and use of convenience foods (DBD905 and DBD910) were asked of participants 12-15 years old, at the mobile examination center (MEC), using the Audio Computer Assisted Self Interviewing (A-CASI) 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 Interviewing (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 of the 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.
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 zero. 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 zero. 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 zero.
Analytic Notes
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 MEC sample weights should be used. Analysis of these questions for 12 to 15 year olds should use the MEC 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 of these are available on the NHANES website.