Guide to Measuring Household Food
Security: Revised 2000
PREFACE TO THE
REVISED EDITION
Since publication of the Guide to Implementing the Core
Food Security Module in 1997 by the Food and Nutrition Service (FNS,
previously Food and Consumer Service) of the U.S. Department of
Agriculture (USDA), the standard procedures for measuring food insecurity
and hunger have undergone further refinement and development based on
ongoing research within the federal interagency Food Security Measurement
Project. This new edition of the Guide documents minor corrections and
changes, bringing the procedures described in the original publication up
to date. These include:
-
Small changes in the format of the core-module
questionnaire for consistency with the form adopted in 1998 for standard
use in the annual Food Security Supplement to the Census Bureau's Current
Population Survey (CPS), and other applications;
-
Significant simplification and streamlining of the recommended
procedure for scoring households with partially missing data;
-
Revised and corrected scale-score ranges, based on 1998 data, for
classifying households by food security status categories;
-
An alternative, simple method of assigning households with complete
core-module data to the food security status-level classifications; and
-
Brief information on adapting the measure for particular survey
uses.
None of these changes alters the content of the food security
core-module questionnaire, the scaling method underlying the food security
scale, or the basic method of classifying households by food security
status level. Consequently, data collections and analyses based on the
original Guide and on this Revised Edition can be fully consistent
(although users of the original Guide should note the corrected and
updated scale-score ranges presented here).
USDA actively encourages State-
and local-area research and population monitoring applications of the
standard national measure of household food security, as well as continued
testing and validation research on the measure itself.
The ERS Food
Security Briefing Room also
provides additional technical information and references.
Introduction
The
presence of hunger in American households due to insufficient resources to
obtain food has been a long-standing challenge to U.S. health, nutrition,
and social policy. The success of the nation's nutrition-assistance safety
net, beginning with the National School Lunch Program in 1946 and later
under-girded by the Food Stamp Program and special programs for unusually
vulnerable groups, has meant that extreme forms of hunger, common in
Third-World countries, have been virtually eliminated in the United
States. However, less severe forms of food insecurity and
hunger--deprivation in basic need for food--are still found within the
U.S. and remain a cause for concern. The basic policy tenet was forcefully
stated by the President's Task Force on Food Assistance in 1984:
It has
long been an article of faith among the American people that no one in a
land so blessed with plenty should go hungry. ...Hunger is simply not
acceptable in our society.
The Task Force also noted that, up to the time
of its Report:
There is no official "hunger count" to estimate
the number of hungry people, and so there are no hard data available to
estimate the extent of hunger directly. .... We regret our inability to
document the degree of hunger caused by income limitations, for such lack
of definitive, quantitative proof contributes to a climate in which policy
discussions become unhelpfully heated and unsubstantiated assertions are
then substituted for hard information.
Now the tools do exist to document
directly the extent of food insecurity and hunger caused by income
limitations, as these conditions are experienced and reported by American
households. Following the 1984 Task Force Report--indeed, in part
stimulated by the report--private-sector researchers redoubled efforts to
develop the kind of direct survey measure that could reliably and
consistently document the extent of U.S. hunger. By the early 1990s, an
extensive body of field experience had been gained and substantial
consensus had emerged among nutrition experts on the sound conceptual and
practical bases for such a measure. Meanwhile, Congress enacted the
National Nutrition Monitoring and Related Research Act of 1990, asserting
the need for better monitoring and assessment of the nutritional state of
the American people. The long-range plan formulated under the Act by the
U. S. Departments of Agriculture (USDA) and Health and Human Services (DHHS)
clarified the government's responsibility to help create a sound national
measure of food insecurity and hunger. A key requirement was that this
measure should be appropriate for standard, consistent use
"throughout the national nutrition monitoring system and at State and
local levels.".
A federal interagency working group--the Food
Security Measurement Project--was formed in 1992 to develop the needed
measure, building upon the earlier research and working in close
collaboration with private-sector experts and the U.S. Census Bureau.
Throughout this development process, one objective held firmly in view was
to make the final measure appropriate and feasible for use in locally
designed and conducted food-security surveys.
We believe that this
objective is achieved with the food-security core survey module, which
currently is being used successfully in local applications throughout the
U.S. and Canada. While the module may seem unduly long and repetitive at
first sight, it generally requires less than four minutes of survey time
to administer--under two minutes average in a full population sample with
screening--while offering important strengths not available from single or
small sets of indicators. The key strength of the measure, as explained
below, is that its multiple indicator questions capture and distinguish
the various levels of severity throughout the full range of severity with
which the phenomenon of food insecurity/hunger is experienced in U.S.
conditions. This feature is critical for accurately assessing the
prevalence of food insecurity because the greater the severity, the less
the prevalence and each separate indicator captures a different degree of
severity. The frequency of the various indicators varies widely depending
upon exactly which level of severity each one reflects.
Food insecurity is
a complex, multidimensional phenomenon which varies through a continuum of
successive stages as the condition becomes more severe. Each stage
consists of characteristic conditions and experiences of food
insufficiency to fully meet the basic needs of household members, and of
the behavioral responses of household members to these conditions. A
variety of indicators is needed to capture the various combinations of
food conditions, experiences, and behaviors that, as a group, characterize
each such stage. This is what the 18-item "core module" set of
indicators provides. The chapters below describe some of the
characteristic aspects of the continuum of food insecurity and hunger, and
Exhibit 3-2 (p.32) illustrates graphically the relationship of the food
security measure to this continuum. An even larger, more detailed
indicator set than the 18-item standard U.S. food security scale might do
an even better job of measuring the severity of food insecurity/hunger--e.g.,
it could distinguish more fully among the various time paths of the
experience (cyclical, episodic, prolonged, brief but intense, etc.) and
among the alternative behavioral paths that reveal the various coping
strategies that households employ in attempting to deal with food-resource
inadequacy. However, for the main purpose of assessing the prevalence of
food insecurity/hunger at each of its several measurable levels of
severity among U.S. households, the 18-item core module has been shown to
be a stable, robust, and reliable measurement tool.
In addition, for
circumstances in which limitations on survey time are insurmountable, a
standard 6-item subset of the core-module indicator questions also has
been developed, designed to capture reliably the first two thresholds
identified in the full continuum measured by the food-security/hunger
scale--i.e., the threshold of identifiable household food insecurity and
the threshold of identifiable hunger among household members. Testing has
shown this standard subset (Appendix B) to be significantly more reliable
in classifying households accurately to the appropriate food security
status level than alternative small, idiosyncratic sets of food-security
indicators selected on impressionistic or "face-validity"
grounds alone.
Local surveys that employ the systematic, tested, and
validated indicator set provided by the core module for food security
measurement, or the reduced standard 6-item partial set, can obtain
findings that are readily interpretable. Such local survey findings can be
compared directly with national and state-level standard benchmark
statistics published annually by USDA and with many national- or
regional-level tabulations of population subgroups available in the USDA
reports. This food security benchmark data series is available from the
U.S. Census Bureau, by CD-ROM or at the Bureau's web-site www.census.gov
or http://ferret.bls.census.gov.
As an additional strength for comparative
research with local survey findings, data from the standard food security
Core Module also will be available from several specialized national
surveys: the 5-year longitudinal Survey of Program Dynamics (SPD,
conducted by the Census Bureau for DHHS, Office of the Assistant Secretary
for Planning and Evaluation), the Early Childhood Longitudinal Study (ECLS,
conducted by the U.S. Department of Education, National Center for
Educational Statistics), the USDA Continuing Survey of Food Intakes by
Individuals (CSFII), and the DHHS 4th National Health and Nutrition
Examination Survey (NHANES-4).
The Core Module has been designed, not only
for use in national surveys, but also for local groups wanting to
determine the extent and severity of food insecurity and hunger within
their own communities, using a technically well grounded and tested method
to produce local prevalence estimates comparable with national and
state-level standard benchmark figures. Local studies using either the
Core Module or the standard 6-item subset can play a key role in
documenting the presence of hunger in the community as measured under
standard national practice, in providing a sound base for broader
community needs assessment, and in helping focus attention on unmet
food-security needs within the community. When the Core Module is used to
collect data on a periodic basis--as USDA is doing for national and state
levels with the annual Food Security Supplement to the Current Population
Survey--it also can provide systematic monitoring of the community's
progress in addressing the hunger and other food-security needs within its
midst.
The next section (Chapter 1) presents the background description of
food security measurement, slightly edited, from the 1997 Guide to
Implementing the Core Food Security Module. The second chapter describes
the data collected with the core module survey instrument. Chapter 3 gives
updated guidance on how to score data collected with the module to produce
prevalence estimates for food insecurity and hunger within the sampled
population. The final chapter offers brief preliminary guidance on
procedures for sampling within local population groups to assure that
findings obtained from food-security surveys can be accurately interpreted
and to avoid making unsupportable generalizations from the data collected.
In general, we recommend that any local group planning a food security
survey seek to work cooperatively with university or other resource
persons experienced in sample-survey work. Numerous sampling methods are
available that are feasible and that can yield meaningful results, but
expertise is needed to design these methods into your planned survey. Some
experienced guidance at the initial planning and design stage of the study
will pay off handsomely in helping to assure that the survey findings you
obtain serve the purposes you intend, and that you and others can make
valid interpretations of the findings.
Last modified: 12/04/2008
|