• Component Description
• Quality Assurance & Quality Control
• Data Processing and Editing
• Analytic Notes
• References
• Codebook
  • SEQN - Respondent sequence number
  • FSD032A - HH Worried run out of food
  • FSD032B - HH Food didn't last
  • FSD032C - HH Couldn't afford balanced meals
  • FSQBOX1 - CHECK ITEM
  • FSD032D - HH Relied on low-cost food for child
  • FSD032E - HH Couldn't feed child balanced meal
  • FSQBOX2 - CHECK ITEM
  • FSQBOX3 - CHECK ITEM
  • FSD032F - HH Child not eating enough
  • FSD041 - HH Adults cut size or skip meals
  • FSD052 - HH How often adults cut size/skip meals
  • FSD061 - HH Eat less than should
  • FSD071 - HH Hungry, but didn't eat
  • FSD081 - HH Lost weight, no money for food
  • FSQBOX4 - CHECK ITEM
  • FSD092 - HH Adults not eat whole day
  • FSD102 - HH How often adults not eat for day
  • FSQBOX5 - CHECK ITEM
  • FSD111 - HH Cut size of child meals
  • FSD122 - HH Child skip meals
  • FSD132 - HH How often child skip meals
  • FSD141 - HH Child hungry in last 12 months
  • FSD146 - HH Child not eat whole day
  • FSDHH - Household food security category
  • FSDAD - Adult food security category
  • FSDCH - Child food security category
  • FSD151 - HH Emergency food received
  • FSQBOX6 - CHECK ITEM
  • FSD401 - Meal size cut
  • FSD411 - Skipped meals
  • FSD421 - Ate less than should
  • FSD431 - Hungry
  • FSQ440 - Lost weight
  • FSQBOX7 - CHECK ITEM
  • FSD451 - Not eat whole day
  • FSQ165 - HH FS benefit: ever received
  • FSQ171 - HH FS benefit: receive in last 12 months
  • FSD225 - HH FS benefit: time since last received
  • FSQ235 - HH FS benefit: amount received last time
  • FSQBOX8 - CHECK ITEM
  • FSQ162 - HH WIC benefit: receive in last 12 month
  • FSQBOX9 - CHECK ITEM
  • FSD650ZC - CH WIC benefit: receive in last 12 month
  • FSD660ZC - CH WIC benefit: currently receive
  • FSD675 - CH WIC benefit: received in infancy
  • FSD680 - CH WIC benefit: received b/w 1-4 yrs old
  • FSD670ZC - CH WIC benefit: # of months received
  • FSQ690 - CH WIC benefit: Mom received while preg.
  • FSQ695 - CH WIC benefit: starting month of preg.
  • FSQBOX10 - CHECK ITEM
  • FSD650ZW - WM WIC benefit: receive in last 12 month
  • FSQBOX11 - CHECK ITEM
  • FSD660ZW - WM WIC benefit: currently receive
  • FSD670ZW - WM WIC benefit: # of months received
• Appendix 1
• Appendix 2

National Health and Nutrition Examination Survey

2007-2008 Data Documentation, Codebook, and Frequencies

Food Security (FSQ_E)

Data File: FSQ_E.xpt

First Published: July 2010

Last Revised: NA

Component Description

The Food Security section (variable name prefix FSQ) provides personal interview data on the following four topics:

1. Household food security
In the household interview, an adult responded to the U.S. Food Security Survey Module (US FSSM) questions (Bickel G, et al, 2000). There are 18 items for households with children under the age of 18 years and 10 items for households without children. Questions refer to all household members, not just NHANES participants. Three categorical household-level variables were created to characterize the overall food security status for the entire household, the adults in the household, and the children in the household. Responses to the 10 or 18 US FSSM items and the categorical data derived from these responses are released on each household participant’s record.

A question on household member’s use of emergency foods from food banks, soup kitchens, or other organizations in the last 12 month is also included in this section.

2. Individual food security
Individual-level food security items were administered to all survey participants in the households that affirmed any FSSM item during the household interview. Adult (≥ 16 years) and children (< 12 years) individual-level food security questions were administered after the 24-hour dietary recall in the Mobile Examination Center (MEC). Generally, adults responded for themselves. An adult family member responded for a child, although the child may have assisted. Adolescents (12-15 years) responded for themselves, in a private room in the MEC, using an Audio Computer-Assisted Self Interview (ACASI) system.

Participants 16 years and older were asked 6 questions about their own food security. Participants under 16 years old were asked 5 questions; the question about having lost weight was not asked of this age group. Most NHANES survey questions that assess a specific aspect of food security are identical or very similar for adults, teens, and children. Similar to the 2005-2006 cycle, data collected separately for different age groups are combined and released as one variable for each topic, although the actual survey instruments may be slightly different by participants' ages. The exact wording of the FSQ questionnaires used in the survey can be found at the NHANES website at: https://wwwn.cdc.gov/nchs/nhanes/search/datapage.aspx?Component=Questionnaire&CycleBeginYear=2007.

These data are released only on the individual participant's record.

3. Food Stamp program benefits
The questions related to Food Stamp program benefits were re-designed for the 2007-2008 data collection. In this cycle, we no longer collected information at the individual level. All Food Stamp benefits questions were collected at the household level. One adult responded to these questions for the entire household during the household interview. Information collected included whether anyone in the household had ever received Food Stamp benefits; whether anyone in the household received benefits in the last 12 months; time since last received benefits within last 12 months; and the amount of benefits the household received last time.

These household-level data on food stamp benefits are released on all household participants’ records.

4. Women, Infants and Children (WIC) program benefits
Data collected for WIC benefits included one household-level question as well as 7 individual-level questions for participants birth to 11 years old and 3 individual-level questions for women 12-59 years old.

In the household interview an adult responded to the question on whether anyone in the household received WIC benefits in the last 12 months. This household-level question is released on all household participants’ records.

For children participants’ WIC benefits, information was collected on current participation, participation in the last 12 month, and total length (in months) of benefits received. Similar to previous cycles, current participation and participation in the last 12 months were ascertained for children 0-5 years of age. In 2007-2008, the target age group for the benefit length question was extended from children 0-5 years of age to 0-11 years old. Also new in this cycle, additional information was obtained on WIC participation during various important periods in early childhood, including prenatal, infancy, and 1-4 years of age. These data were collected through adult proxy during the household interview as part of the Dietary Behavior and Nutrition questionnaire (DBQ) and released on the individual participant’s record.

For female participants 12 to 59 years of age, information was collected on current WIC participation, participation in the last 12 month, and total length (in months) of benefits received. These questions were administered as part of the Reproductive Health questionnaire (RHQ) during the interview in the MEC, using the Computer-Assisted Personal Interviewing-CAPI (interviewer administered) system. Due to disclosure risks, the WIC benefits data will only be released for women aged 20 years and above in the present dataset. Data for women 12-19 years old will be available in the Research Data Center (RDC) only. Please refer to the Analytic Notes section for more details.

The table in Appendix 1 provides detailed information on each of the four FSQ components described above. Appendix 2 highlights the changes in the FSQ section among the latest three release cycles.

Quality Assurance & Quality Control

The automated interview systems used in NHANES are programmed with built-in consistency checks to reduce data entry errors. Incoming FSQ data were reviewed for accuracy and completeness. NHANES staff reviewed taped interviews, traveled to field sites to observe interviews, read interviewer comments, and attended training and re-training sessions to maintain the high quality of data.

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.

FSDHH, FSDAD, FSDCH (Household, adult, and child food security category)
Eighteen FSSM questions were asked of households with children under the age of 18. Ten questions were asked of households without children. Three categorical variables, each with four response levels, were created based on the number of affirmative responses for those questions. These categorical variables could be used to characterize the overall food security status for the entire household, the adults in the household, and the children in the household. The algorithms used to derive these categorical variables are described below:

FSDHH (Household food security category):

Count affirmative responses in these 18 items: FSD032a, FSD032b, FSD032c, FSD032d, FSD032e, FSD032f, FSD041, FSD052, FSD061, FSD071, FSD081, FSD092, FSD102, FSD111, FSD122, FSD132, FSD141, and FSD146. Derive the codes as the following:

1 = Household full food security: no affirmative response in any of these items.
2 = Household marginal food security: 1-2 affirmative responses.
3 = Household low food security: 3-5 affirmative responses for household without children under the age of 18; 3-7 affirmative responses for household with children
4 = Household very low food security: 6-10 affirmative responses for household without children under the age of 18; 8-18 affirmative responses for household with children

Households with children but provided no valid response to any of the questions about children’s food security were classified using the specifications for households with no child.

FSDAD (Adult food security category):

Count affirmative responses in these 10 items: FSD032a, FSD032b, FSD032c, FSD041, FSD052, FSD061, FSD071, FSD081, FSD092, and FSD102. Derive the codes as the following:

1 = Adult full food security: no affirmative response in any of these items.
2 = Adult marginal food security: 1-2 affirmative responses.
3 = Adult low food security: 3-5 affirmative responses
4 = Adult very low food security: 6-10 affirmative responses

For households without children under the age of 18, their household food security category (FSDHH) should be identical to their adult food security category (FSDAD).

FSDCH (Child food security category):

This category is only generated for households with children under the age of 18. Count affirmative responses in these 8 items: FSD032d, FSD032e, FSD032f, FSD111, FSD122, FSD132, FSD141, and FSD146. Derive the codes as the following:

1 = Child full or marginal food security: no affirmative response in any of these items.
2 = Child marginal food security: 1 affirmative response.
3 = Child low food security: 2-4 affirmative responses.
4 = Child very low food security: 5-8 affirmative responses.

The labels used to describe ranges of food security in this category are slightly modified, based on USDA's recommendation, for this release cycle.

Definition of FSSM affirmative response

Affirmative response for FSSM questions are defined as:

• Answered "often true" or "sometimes true" (i.e., codes 1 or 2) for items FSD032a, FSD032b, FSD032c, FSD032d, FSD032e, or FSD032f.
• Answered "yes" (i.e., code 1) for items FSD041, FSD061, FSD071, FSD081, FSD092, FSD111, FSD122, FSD141, or FSD146.
• Answered "almost every month", or "some months but not every month" (i.e., codes 1 or 2) for items FSD052, FSD102, or FSD132.

No food security categories are assigned if all or most of these items were answered as "don't know" or "refusal". There are 9 such records in the 2007-2008 dataset, two of them from households with children. These records contain missing values for FSDHH, FSDAD, and FSDCH.

FSD451 (Not eat for whole day)
Because responses other than "Never" were very rare for FSQ451, responses of "often" and "sometimes" were collapsed into one category, "ever" in the released variable.

FSD225 (Time since last received Food Stamp benefits)
During the household interview, the respondent was asked to report the date that the household last received Food Stamp benefits. A variable was then derived by calculating the number of days between the time the household last received the Food Stamp benefit and the date of interview and released as FSD225.

When the respondent refused to answer the question or did not know the exact date, a follow-up question (FSQ230) was asked to see whether any members of the household currently receive Food Stamp benefits. For these households, the answer to FSQ230 was used to derive the codes 55555 (current HH FS benefits recipient, last received date unknown) and 66666 (non-current HH FS benefits recipient, last received date unknown) for variable FSD225.

FSD670ZC, FSD670ZW (Number of months the participant received WIC benefit)
This information was collected using two-part (number and unit) questions to allow respondents to report the length in either month or year. The released variables were edited to standardize the reported length to number of months. 

Seven respondents reported that the child received WIC for more than 60 months, even though children are only eligible for the program up until their 5th birthday. All of these respondents also indicated on FSQ690 that the mother of the child received WIC while she was pregnant with the child, which may explain why answers greater than 60 were given.

WIC data for women that appeared unlikely (e.g. a mother receiving WIC for longer than WIC regulations stipulate) were not edited either, as there are plausible explanations for longer WIC intake.

FSD650ZW (Women received WIC benefit in last 12 month)
Similar to previous data collection cycles, this question only asked of female participants who were pregnant at the time of interview or who had given birth in the two years period prior to the interview.

FSD660ZW (Women currently received WIC benefit)
This question only asked of female participants who received WIC benefits in the last 12 months, and were pregnant or 0-12 months postpartum at the time of interview. The postpartum screening criterion for this question is a new addition in 2007-2008. It helps to better classify eligibility for WIC benefit.

Analytic Notes

NHANES has assessed household food security with the U.S. Food Security Survey Module (US FSSM) since 1999. Individual-level food security items for adults and children were implemented in the survey in 2000, and added for adolescents in 2005. Similar modules have been used in various surveys, including the Census Bureau's Current Population Survey (CPS) and a growing number of State, local, and regional studies, such as the California Health Interview Survey (CHIS). For more information on food security measurement, please refer to the USDA’s website at: http://www.ers.usda.gov/Briefing/FoodSecurity.

The NHANES household interview included two questionnaires: a sample person questionnaire to collect information regarding each individual survey participant’s personal health status, and a family questionnaire to collect information at the family level, such as total income for the family, food availability in the family, etc. The sample person questionnaire was answered by participants themselves (adult proxy for child under 16 years old). The family questionnaire required an adult family member, preferably the head of the family, to respond to these questions for the entire family. The information on household food security status and Food Stamp program benefits in the FSQ section were collected as part of this family questionnaire. In 2007-2008, 77 participants have missing values to all of these items in the FSQ section because the family questionnaire was not administered. Most common reasons for missing the family questionnaire interview were no eligible adult respondent in the family available or refusal.

The eligibility of the individual food security questions was determined by the reported household food security status. The abovementioned 77 participants who did not have food security data reported for their household were not eligible for the individual food security questions collected in the MEC. In this dataset, there were 280 participants who were eligible to the individual food security questions but did not have data in these items. 239 of them did not come to the MEC exam or missed the interview when they were in the exam center due to various reasons (such as arrived late/left early, refusal, illness, emergency, or equipment failure). 41 of them missed the individual food security questions because their family questionnaire data were collected or uploaded to the system after their examinations in the MEC.

In 2007-2008, a new sample design was implemented to the survey. All Hispanics were oversampled, not just Mexican Americans. In addition, for each of the race/ethnicity domains, the 12-15 and 16-19 year age domains were combined and the 40-59 year age minority domains were split into 10 year age domains 40-49 and 50-59. This has led to an increase in the number of participants aged 40+ and a decrease in 12-19 year olds from previous cycles. Lastly, pregnant women were no longer oversampled. Based on these changes, unweighted frequencies of certain variables may differ slightly in this survey cycle compared to earlier survey cycles. For further discussion, please see the Analytic Notes for the Demographic data file: https://wwwn.cdc.gov/nchs/nhanes/2007-2008/demo_e.htm.

WIC benefit information was collected for female participants 12 to 59 years of age in 2007-2008. Due to potential disclosure risks, this file does not include data of WIC benefit related variables for females less than 20 years old. For female participants 12-19 years old, records are coded as missing for the following variables: FSD650ZW, FSD660ZW, and FSD670ZW. Please note that these exclusions were not made to earlier releases of the FSQ data files. Analysts wishing to combine data for multiple years should pay careful attention to these changes. The complete data file containing all variables for females 12 years and older (FSQ_E_R) is available through the NCHS Research Data Center.

FSQ data were collected in the household and in the MEC. For data items collected in the household interview, the interview sample weights may be used in their analysis. However, if the data analysis requires merging of data collected in the household with data collected in the MEC, examination sample weights should be used for analyses. The recommended weights for each individual component in the FSQ section are listed in the table in Appendix 1. 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.

 

References

• Bickel G, Nord M, Price C, Hamilton W, Cook J. Guide to Measuring Household Food Security Revised 2000.  U.S. Department of Agriculture, Food and Nutrition Service, Alexandria VA. March, 2000. Available from: http://www.fns.usda.gov/sites/default/files/FSGuide_0.pdf

Codebook and Frequencies