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The food security statistics reported by ERS are based
on a survey measure developed by the U.S. Food Security
Measurement Project, an ongoing collaboration among Federal
agencies, academic researchers, and private commercial
and nonprofit organizations. The measure was developed
in response to the National Nutrition Monitoring
and Related Research Act of 1990 (NNMRR).
The Ten-Year Comprehensive Plan developed
under that Act specified the following task: "Recommend
a standardized mechanism and instrument(s) for defining
and obtaining data on the prevalence of 'food insecurity'
or 'food insufficiency' in the United States and methodologies
that can be used across the NNMRR Program and at State
and local levels."
Beginning in 1992, USDA staff reviewed
the existing research literature on the conceptual basis
for measuring food insecurity and on the practical problems
of developing a survey instrument for use in sample surveys
at national, State, and local levels. 
In January 1994, USDA's Food and Nutrition
Service (FNS) joined with the U.S. Department of Health
and Human Services' National Center for Health Statistics
to sponsor a National Conference on Food Security
Measurement and Research. The conference brought
together leading academic experts, private researchers,
and key staff of the concerned Federal agencies. The conference
identified the appropriate conceptual basis for a national
measure of food insecurity. The conference also reached
a working agreement as to the best operational form for
implementing such a measure in national surveys.
The CPS Food Security Supplement 
The U.S. Census Bureau carried out a cognitive assessment
and field test of the food security questionnaire. They
finalized the questionnaire and administered it as a supplement
to the Current Population Survey (CPS) of April 1995.
The Food Security Supplement was repeated
again in September 1996, April 1997, August 1998, April
1999, September 2000, April and December 2001, and annually
in December since 2001. Minor modifications to the questionnaire
format and screening procedures were made over the first
several years, and a more substantial revision in screening
and format, designed to reduce respondent burden and improve
data quality, was introduced with the August 1998 survey.
However, the content of the 18 questions upon which the
U.S. Food Security Scale is based remained constant in
all years.
Development of the Household Food Security Scale
Initial
analysis of the 1995 data was conducted by Abt Associates
Inc. through a cooperative venture with FNS, an interagency
working group on food security measurement, and other
key researchers involved in developing the questionnaire.
The Abt team used nonlinear factor analysis and other
state-of-the-art statistical methods to produce a scale
that measures the severity of deprivation in basic food
needs as experienced by U.S. households. Extensive testing
established the validity and reliability of the scale
and its applicability across various household types in
the broad national sample.
Following collection of the September 1996 and April
1997 CPS food security data, Mathematica Policy Research,
Inc. (MPR), under a contract awarded by FNS, independently
reproduced the results from the 1995 CPS food security
data, estimated prevalence rates of food insecurity for
1996 and 1997, and assessed the stability and robustness
of the measurement model when applied to the separate
datasets. The
MPR findings established the stability of the food
security measure over the 1995-97 period. That is, the
relative severities of the items were found to be nearly
invariant across years and across major population groups
and household types.
ERS Assumes Sponsorship of the Food Security Survey
In 1998, the Economic Research Service (ERS) assumed
sponsorship of the Census Bureau's annual food security
survey and responsibility for analyzing and reporting
the data and for coordinating ongoing USDA research on
food security and food security measurement.
ERS collaborated with MPR and FNS to develop and finalize
standardized procedures for calculating the household
food security scale and analyzed the data from 1998 and
later years using these procedures. ERS and IQ Solutions
analyzed data from
the 1998 and 1999 surveys, found that the scale continued
to be stable, and examined additional technical measurement
and estimation issues.
Committee on National Statistics Reviews the Food Security
Measure
In 2003-06 an expert panel convened by the Committee
on National Statistics (CNSTAT) of the National Academies
conducted a thorough review of the food security measurement
methods. USDA requested the review to ensure that the
measurement methods USDA uses to assess households’
access—and lack of access—to adequate food
and the language used to describe those conditions are
scientifically sound and that they convey useful and relevant
information to policy officials and the public. The panel
convened by CNSTAT to conduct this study included economists,
sociologists, nutritionists, statisticians, and other
researchers. Two of the central issues the CNSTAT panel
addressed were whether the concept and definition of hunger
were appropriate for the policy context in which food
security statistics are used, and whether the relationship
between hunger and food insecurity was appropriately represented
in the language used to report food security statistics.
The CNSTAT
panel recommended that USDA continue to measure and
monitor food insecurity regularly in a household survey,
affirmed the appropriateness of the general methodology
currently used to measure food insecurity, and suggested
several ways in which the methodology might be refined
(contingent on confirmatory research).
The CNSTAT panel recommended that USDA make a clear and
explicit distinction between food insecurity and hunger
and consider alternative labels to convey the severity
of food insecurity without using the word "hunger."
USDA concurs with this recommendation and, accordingly,
has introduced the new labels
"low food security" and "very low food
security" to replace "food insecurity without
hunger" and "food insecurity with hunger,"
respectively. USDA is collaborating with partners in the
food security measurement community to explore how best
to implement other recommendations of the CNSTAT panel.
The Federal food security measurement project has developed
standardized questionnaires and methods for editing and
scoring to produce household summary measures of food
security status. These modules are now in use in several
national surveys including:
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