Component Description
The Diet Behavior and Nutrition (DBQ) section provides personal interview data on several nutrition topics. Many of the questions in the NHANES 1999 DBQ section were included in NHANES II, 1976-80, Hispanic HANES 1982-84, and NHANES III, 1988-94. There are different target age groups for the topics in this section. For example, the questions pertaining to infant nutrition and breast-feeding were asked of proxy respondents for children 6 years of age and younger; alcohol consumption frequency questions were asked of persons 20+ years of age; and senior meal program participation questions were asked of respondents 60+ years of age. Data users should review the survey questionnaire thoroughly to determine the appropriate population targeted for each topic.
Topics and the target population groups in the DBQ section:
- Breastfeeding and other childhood feeding practices (< 6 yr)
- Restaurant meal frequency (≥1 yr)
- Table salt use and salt type used (≥1 yr)
- Dark green vegetables and dried beans or peas consumption frequency
(≥2 yr)
- Poultry consumption (yes/no) and poultry skin trim practices (≥12 yr)
- Meat consumption (yes/no) and meat fat trim practices (≥12 yr)
- Current milk consumption pattern and types of milk (≥1 yr)
- Milk consumption pattern throughout the life span (≥20 yr)
- Alcohol consumption frequency by type of alcohol (≥20 yr)
- Food consumption practices for elderly (≥60 yr):
- Screener for servings of 5 major food groups
- Home-delivered meals in the past 12 months
- Meals eaten at community feeding site in the past 12 months
- School meal program participation (4-19 yr)
Eligible Sample
The target age groups for questions in this section vary. Please review the questionnaire and codebook carefully.
Data Processing and Editing
Edit decisions were made to ensure the completeness, consistency, and analytic usefulness of the data. Systematic data editing was conducted to:
- Standardize the reported age for questions on breastfeeding and other childhood feeding practices to number of days (DBD020, DBD030, DBD040, DBD050, DBD060, and DBD080). These variables were derived from the two-part (number and unit) questions DBQ020, DBQ030, DBQ040, DBQ050, DBQ060, and DBQ080 using the conversion factors 7 days/week, 30.4 days/month and 365days/year. If reported age was less than the current age at interview, the value was recorded as missing.
- Combine response categories for type of milk reported in questions DBQ070 and DBQ220. The type of milk consumed was originally collected with a10-item list:
- whole or regular,
- 2% fat milk (includes "low fat milk" not further specified),
- 1% fat milk,
- skim, nonfat, or 0.5% fat milk (includes liquid or reconstituted from dry),
- evaporated milk, whole milk,
- evaporated milk, skim milk,
- buttermilk,
- goat’s milk,
- soy or imitation milk, and
- another type.
Due to low frequencies of responses, items 5-10 were combined into one category ("Other types") to ensure adequate cell sample sizes for analysis. Note that responses to these questions are collected as "code all that apply." A respondent could report more than one type of milk consumed and all responses were recorded.
- Standardize responses to the restaurant meal question (DBD090). Respondents were asked how many times per week they had eaten meals prepared in a restaurant. The number of times was reported as per week, never, or less than weekly. If the frequency was reported as "never," the value was recorded as zero. If the frequency was reported as " less than weekly," the value was recorded as "6666".
- Standardize the frequency of current milk consumption reported (DBD195). During NHANES1999, frequency of milk consumption during the past 30 days was collected for participants aged 1 year and above with a two-part (number and unit) question DBQ200. Based on feedback from the field, this question was changed to a question with multiple response categories (DBQ195) at the start of NHANES 2000 data collection. With the revised question (DBQ195), the frequency of milk consumption was reported as never, rarely (less than once a week), sometimes (once a week or more, but less than once a day), or often (once a day or more). During data processing, frequency data collected during the first year were first converted into number of times per week using the conversion factors 7 days/week and 30.4 days/month. The
derived frequencies were subsequently converted into the current categories and included in the dataset.
- Standardize the frequency of milk consumption reported during different ages in life (DBD235a, DBD235b and DBD235c). During NHANES 1999, participants aged 20 years and above were asked to recall frequency of milk consumption when they were a child (ages 5-12 years), a teenager (ages 13-17 years) and a young adult (ages 18-35 years). Frequency of milk consumption was collected with a two-part (number and unit) question DBQ230. Based on feedback from the field, this question was changed to a question with multiple response categories (DBQ235) at the start of NHANES 2000 data collection. With the revised question (DBQ235), the frequency of milk consumption was reported as never, rarely (less than once a week), sometimes (once a week or more, but less than once a day), or often (once a day or more). During data processing, frequency data collected during the first year were first converted into number of times per week using the conversion factors 7 days/week and 30.4 days/month. The derived frequencies were subsequently converted into the current categories and included in the dataset.
- Standardize the frequency of alcohol consumption reported to number of times per month (ALD240, ALD250, and ALD260). These variables were derived from the two-part (number and unit) questions ALQ240, ALQ250, and ALQ260, using the conversion factors 7 days/week and 30.4 days/month. If the frequency was reported as "never," the value was recorded as zero. It is important to note that the portion sizes were not defined, and responses represent "number of times" as determined by the respondent.
- Standardize the frequency of food consumption reported to number of helpings per day (DBD270a, DBD270b, DBD270c, DBD270d and DBD270e). Respondents aged 60 years and above were asked how many helpings of specified foods they had eaten on an average day. Foods asked in the question are grouped into five categories: protein foods, milk or daily products, fruits or fruit juices, vegetables, and bread or grains. The number of helpings consumed was reported as per day or never. If the frequency of consumption was reported as "never," the value was recorded as zero. It is important to note that the sizes of helpings were not defined, and responses represent "number of helpings" as determined by the respondent.
The following three questions were not included in the Survey until the beginning of 2000. To ensure consistent sample sizes across questionnaire components, these questions were not included in the NHANES 1999-2000 Public Data Release File.
- Dark green vegetable consumption (DBQ102). Frequencies were reported as number of times per day, per week, per month, per year, or never for the past 12 months.
- Dried beans or peas consumption (DBQ103). Frequencies were reported as number of times per day, per week, per month, per year, or never for the past 12 months.
- Self-appraisal as a lifetime regular milk drinker (DBQ228). A regular milk drinker was defined as "uses any type of milk at least 5 times a week." Based on this definition, the respondent was asked to classify himself as either a regular milk drinker for most or all of his life, never a regular drinker, or a milk drinker with varied drinking habits over his life.
Analytic Notes
Special Notes on Using the Dataset
In this section, frequency of alcohol consumption during the past 30 days was collected for participants aged 20 years and older by alcohol type. There is additional information on alcohol use in the Survey, including: 1) 24-hour dietary recall data on alcohol consumption which can be used to quantify the contribution of alcohol to total food energy intake and produce population reference data on alcohol intake; 2) MEC interview data on quantifiable current alcohol use and life time drinking behavior for adults aged 20 years and above; and 3) MEC Audio-CASI data on alcohol use in adolescents aged 12-19 years old. Please refer to the documentation and codebooks for these sections for data analysis.