Food Assistance & Nutrition

 Research Program

Measuring Children's 

Food Security in U.S. 

Households, 1995-99

Measuring Food Security in the United States

United States

Department of

Agriculture

Economic 

Research

Service

Food Assistance

and Nutrition

Research Report

Number 25

Mark Nord and Gary Bickel
Measuring Children’s Food Security in U.S. Households, 1995-99. By Mark Nord

and Gary Bickel. Food and Rural Economics Division, Economic Research Service, U.S.

Department of Agriculture. Food Assistance and Nutrition Research Report No. 25.

Abstract

The capacity to accurately measure the food security status of children in household

surveys is an essential tool for monitoring food insecurity and hunger at the most

severe levels in U.S. households and for assessing programs designed to prevent or

ameliorate these conditions. USDA has developed a children’s food security scale to

meet this measurement need. The scale is calculated from 8 questions in the 18-item

food security survey module that ask specifically about food-related experiences and

conditions of children. The scale measures the severity of food insecurity among

children in surveyed households and identifies—in the most severe range of the

scale—households in which children have been hungry at times because of a lack of

household resources for food. The reliability of the children’s food security scale is

assessed, and the scale is compared with the household-level food security scale.

Details are provided on how to calculate the children’s food security scale from the

questions in the standard food security survey module. The prevalence of hunger

among children in U.S. households is estimated by applying the newly developed

children’s food security scale to data from the nationally representative Current

Population Survey Food Security Supplements for the years 1995-99. Prevalence

estimates are presented for all U.S. households and for subgroups defined by household structure, race and ethnicity, income, and rural/urban residence.

Acknowledgments

The authors thank Margaret Andrews, John Cook, Joda Derrickson, Mary Hama, Chris

Hamilton, and Kathy Radimer for valuable comments on the paper. An earlier version

of the paper was presented at the Second Food Security Measurement Conference in

Alexandria, Virginia, February 23-24, 1999, co-sponsored by the Economic Research

Service and the Food and Nutrition Service, USDA, and the National Center for

Health Statistics, DHHS.

1800 M Street, NW

Washington, DC 20036-5831 April 2002
Contents

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .iii

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

Chapter 1

The Prevalence of Hunger Among Children in U.S. Households . . . . . . . . . . . . . .4

Chapter 2

The Children’s Food Security Scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

Chapter 3

Why the Children’s Food Security Scale Is More Reliable Than the

Household Scale for Identifying Hunger Among Children . . . . . . . . . . . . . . . .21

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28

Appendix A

The U.S. Household Food Security Survey Module . . . . . . . . . . . . . . . . . . . . . . .29

Appendix B

Implementing the Children’s Food Security Scale . . . . . . . . . . . . . . . . . . . . . . . .33

ii  Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25 Economic Research Service/USDA
Summary

The ability to accurately measure the food security status of children in household

surveys is an essential tool for monitoring food insecurity and hunger at the most

severe levels in U.S. households and for assessing programs designed to prevent or

ameliorate these conditions. A tool for this purpose, the “children’s food security

scale” has been developed by USDA. The children’s food security scale is based on 8

questions in the 18-item food security survey module that ask specifically about foodrelated experiences and conditions of children. It measures the severity of food

insecurity among children in surveyed households and identifies households in which

children were hungry at times during the previous year because the household lacked

enough money for food. 

Applied to survey data from the nationally representative Current Population Survey

Food Security Supplements, the new measure indicates that during the year ending in

April 1999, children were hungry at times in 219,000 U.S. households, or 0.6 percent

of all households with children. The corresponding statistic for the year ending in

August 1998 was 331,000 households, representing 0.9 percent of all households

with children. 

To provide more stable prevalence estimates for subpopulations, statistics are averaged

across 2 years, 1998-99. The average annual prevalence of hunger among children

during this 2-year period was 0.7 percent. The prevalence of hunger among children

was higher in single-mother families (1.8 percent) and in families headed by Blacks

(1.3 percent) and Hispanics (1.4 percent).

The prevalence rate of children’s hunger declined from 1995, when household food

security and hunger were first measured nationally in the United States, to 1999.

During this period, the prevalence of children’s hunger declined by about half, from

1.1 percent of all households with children in 1995 to 0.6 percent in 1999. The fall in

hunger prevalence among children extended to all major demographic and income

categories, including those most vulnerable to hunger. 

The children’s food security scale is assessed statistically and found to be adequately

reliable and to be stable across years. The scale is compared with the household-level

food security scale, and discrepancies between the two scales are found to result from

identifiable household characteristics, especially the ages of children. Details are provided on how to calculate the children’s food security scale from the questions in the

standard food security survey module.

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  iii
Introduction

An important objective of public policy in the United

States for more than 50 years has been to reduce, and

ultimately to eliminate, childhood hunger in America.

Food sufficiency and diet quality have long been recognized as vital for children’s health, development, and

general well-being. Beginning with the National

School Lunch Program in 1946, several of the major

Federal food assistance programs have been aimed

specifically at assuring adequate nutrition for children.

The capacity to accurately measure the food security

status of children in household surveys and to identify

the occurrence of resource-constrained hunger among

children is an essential tool for monitoring the prevalence of children’s hunger and for assessing programs

designed to address it. Developing appropriate methods

to meet this need has been a prime objective of the

Federal interagency food security measurement project

in recent years.1

The Federal Government has measured and reported

the extent and severity of food insecurity and hunger

in U.S. households annually since 1995, including

estimates of the number of children in food-insecure

households and in households with one or more members going hungry at times because of lack of money

for food. However, the total number of children in all

households with hunger substantially overstates the

number of children experiencing hunger. In most such

households, only adult members go hungry, while the

children—especially young children—are shielded by

adults from that more severe level of food deprivation

(Hamilton et al., 1997a).

On the other hand, the initial effort made to identify

households in which children had been hungry by

means of a more severe category of the household scale

had the opposite bias, i.e., it understated the number of

households with hunger among children. Hamilton et

al. (1997a; 1997b), in the initial development of the

household-level food security measure, specified a

“severe hunger” category that was intended primarily to

identify households with hunger among children. This

effort to find such a proxy measure for children’s

hunger was consistent with the objective of the project

at that time to develop a single, unified, householdlevel measure of severity. A substantial body of earlier

research had found that, in the United States, children

are generally shielded from hunger at less severe levels

of household deprivation, including some level of

hunger among adults. Typically, children begin to

experience hunger only when hunger among adults in

the household reaches more severe levels, e.g., when

adults go whole days without eating. The householdlevel data from the Current Population Survey (CPS)

Food Security Survey strongly confirmed these earlier

findings, lending support to the idea that a “severe

hunger” category of the general household measure

could provide an acceptable proxy for households with

children’s hunger.2 However, further examination

showed that not all households with children conform

to the modal pattern of not reporting hunger among

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  1

Measuring Children’s Food Security

in U.S. Households, 1995-99

Mark Nord and Gary Bickel

1 The Federal interagency food security measurement project

was organized in response to the National Nutrition Monitoring

and Related Research Act of 1990, and the Ten-Year Plan developed under the Act. The project, under the leadership of USDA

and DHHS, was assigned the task of developing “a standardized

mechanism and instrument(s) for defining and obtaining data on

the prevalence of ‘food insecurity’ or ‘food insufficiency’ in the

U.S. and methodologies that can be used across the [National

Nutrition Monitoring] Program and at State and local levels.” For

further information on the project, see Hamilton et al. (1997a) and

Carlson, Andrews, and Bickel (1999).

2 The CPS Food Security Survey is fielded annually as the Food

Security Supplement to the Census Bureau’s regular Current

Population Survey (CPS). USDA sponsors collection of the Food

Security Supplement while the Bureau of Labor Statistics sponsors

the monthly labor-force core of the CPS. The shorter “CPS Food

Security Survey” designation is used throughout this report for

ease of communication.

Measuring Food Security in the United States
children until adult hunger in the household reaches a

severe level (such as adults going a whole day without

eating). Evidence of children’s hunger is reported in a

substantial number of households that have only moderate hunger among adults. It became apparent,

therefore, that the prevalence of children’s hunger is

understated by the prevalence of “severe hunger” as

measured at the household level (Carlson et al., 1999).

To address this concern and to achieve valid estimates

of the prevalence of hunger among children, a new

children’s food security scale has been developed,

building on 5 years of analysis of CPS Food Security

Survey data.3 This children’s food security scale is

calculated from eight survey items that ask specifically about food-related experiences and conditions of

children in the household. The scale’s purpose is to

measure the food security status of children and,

specifically, to identify households in which one or

more children have been hungry at times during the

year because there was not enough money for food in

the household. 

The 8 child-referenced items are a subset of the 18

survey items on which the household food security

scale is based (see appendix A for the full food

security survey module). Like the household- and

adult-referenced items in the scale, the child-referenced items ask about food deprivation experiences

and conditions across a wide range of severity. For

example, the least severe child-referenced item is:

“We relied on only a few kinds of low-cost food to feed

the children because we were running out of money to

buy food.” Was that often, sometimes, or never true for

you in the last 12 months?

An item at midrange is:

In the last 12 months, did you ever cut the size of the

children’s meals because there wasn’t enough money

for food?

And the most severe item is:

In the last 12 months, did any of the children ever not

eat for a whole day because there wasn’t enough

money for food?

Households that affirmed five or more of the eight

child-referenced items are classified as having hunger

among children. Typically, a household just past the

threshold of this severity range will have affirmed all

of the following:

1. They relied on only a few kinds of low-cost food to

feed the children because they were running out of

money to buy food;

2. They couldn’t afford to feed the children balanced

meals;

3. The children were not eating enough because the

household just couldn’t afford enough food;

4. They cut the size of children’s meals because there

wasn’t enough money for food;

5. The children were hungry but they just couldn’t

afford more food.

All of the items in the scale are presented and discussed in detail in chapter 2.

Two aspects of the scale should be kept in mind when

interpreting the prevalence rates in this report. First,

although this new measure is child-specific, it is still a

household-level scale. That is, it identifies households

with hunger among children. More precisely, it identifies households in which at least one child (age 0-17)

has been hungry at times during the year because of

constrained household resources. This does not mean

that all children in the household necessarily were

hungry. Research described in later chapters shows

that younger children are protected from hunger and

reduced food intake at much more severe levels of

adult deprivation than are older children. The CPS

Food Security Survey does not ask about the experience of each child separately, but only about whether

any child in the household experienced the various

forms of food deprivation. Thus, when a household

with several children of varying age affirms items

evidencing children’s hunger, this may mean that all

the children were hungry at times because of constrained household resources, or it may mean that an

older child was hungry while younger children were

shielded from hunger. 

2  Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25 Economic Research Service/USDA

3 This children’s food security scale was initially described in

Nord and Bickel, 1999.
Thus, the number of children living in households with

children’s hunger provides an upper-bound estimate of

the actual number of hungry children in the Nation. A

lower-bound estimate is provided by the number of

households with hungry children, since at least one

child in each of these households has been hungry

because of a lack of money for food. The substantial

difference between these upper- and lower-bound estimates are inherent in the CPS Food Security Survey

design. Thus, while the statistics presented in this

report are the most reliable currently available, they do

not provide a highly precise answer to the question,

“How many hungry children are there in the Nation?”

The second aspect of the scale that should be kept in

mind is that it describes experiences and conditions

over the entire 12-month period preceding the survey.

Nationally, children in 219,000 U.S. households were

hungry at times during the year that ended in April

1999 because of the households’ food insecurity. This

does not mean that these households were unable to

provide enough food for the children every day, or

even every month.

Research reported elsewhere suggests that the number

of households with hunger among children some time

during an average month is about 60 percent of the

annual prevalence rate, while the daily prevalence is

lower still—about 13 percent of the annual rate (Nord,

Andrews, and Winicki, 2000). 

Chapter 1 summarizes the annual prevalence of

hunger among children in U.S. households, based on

the children’s food security scale. Prevalence rates of

hunger among children in 1998 and 1999 are presented for all U.S. households with children and by

household structure, race and ethnicity, income, and

rural/urban residence. Annual trends are summarized

from 1995 to 1999. Information from the household

food security scale is then combined with information

from the children’s food security scale to provide a

broader picture of the food security situation of the

Nation’s children.

The remainder of the report documents the measurement methodology. Chapter 2 describes the children’s

food security scale and discusses theoretical, statistical, and methodological issues regarding it. Chapter 3

explores the relationship between the hunger range of

the children’s food security scale and the conceptually

similar “severe-hunger” range of the household scale.

Appendix A presents the questions in the food security

core survey module, and appendix B describes how to

calculate the children’s food security scale from the

child-specific items in the core module.

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  3
During the year ending in April 1999, one or more

children were hungry at times in 219,000 U.S. households, or 0.6 percent of all households with children

(table 1). The comparable statistic for the year ending

in August 1998 was 331,000 households, representing

0.9 percent of all households with children.

The difference between the 2 years represents, in part,

a decline in the prevalence of hunger among children,

4  Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25 Economic Research Service/USDA

Chapter 1

The Prevalence of Hunger Among 

Children in U.S. Households

Overview

Table 1—Households with hunger among children, 1998 and 1999

Total households with children Households with hunger among children

Household characteristics 1998 1999 Average 1998 1999 Average 1998 1999 Average

------------------------------------------------------------------------1,000----------------------------------------------------------- --------------------Percent---------------------

All households with children 38,036 37,884 37,960 331 219 275 0.9 0.6 0.7

Household structure:

Married-couple families 26,306 26,303 26,305 105 75 90 .4 .3 .3

Female head, no spouse 8,807 8,744 8,775 193 123 158 2.2 1.4 1.8

Male head, no spouse 2,153 2,187 2,170 20 17 19 .9 .8 .9

Other households with child1 770 650 710 14 3 9 1.8 .5 1.2

With children under age 6 17,087 17,231 17,159 85 69 77 .5 .4 .4

Race and ethnicity:2

White non-Hispanic 25,750 25,431 25,591 145 95 120 .6 .4 .5

Black non-Hispanic 5,645 5,413 5,529 98 54 65 1.7 1.0 1.3

Hispanic3 4,844 5,373 5,109 76 54 76 1.6 1.0 1.4

Other non-Hispanic 1,797 1,667 1,732 13 15 14 .7 .9 .8

Household income-to-poverty ratio:

Under 1.00 6,012 5,701 5,857 178 111 144 3.0 1.9 2.5

Under 1.30 (includes under 1.00) 8,162 7,583 7,872 238 129 184 2.9 1.7 2.3

Under 1.854 (includes under 1.30) 12,777 11,702 12,239 282 177 229 2.2 1.5 1.9

1.85 and over4 21,943 22,504 22,224 37 38 38 .2 .2 .2

Area of residence:

Inside metropolitan area 30,729 30,790 30,759 251 193 222 .8 .6 .7

In central city5 9,160 9,004 9,082 112 64 88 1.2 .7 1.0

Not in central city5 16,210 16,616 16,413 118 104 111 .7 .6 .7

Outside metropolitan area 7,308 7,094 7,201 80 26 53 1.1 .4 .7

1 Households with children in complex living arrangements, e.g., children of other relatives or of unrelated roommate or boarder.

2 Race/ethnicity of household reference person.

3 Hispanics may be of any race.

4 Subtotals do not add to national total because income is not reported for 8.7 percent of households.

5 Subtotals do not add to metropolitan area total because central city residence is not identified for some households.

Source: Calculated by ERS from Current Population Survey Food Security Supplement data, August 1998 and April 1999, based on the children’s food 

security scale.
and in part a seasonal difference (Andrews et al.,

2000). The CPS Food Security Survey has been

administered in the spring and fall in alternate years.

Even though the questions ask about experiences and

conditions over the past 12 months, there is evidence

of a moderate seasonal effect in the measured prevalence rates of household food insecurity and hunger,

with rates being somewhat higher in the fall (Andrews

et al., 2000). For this reason, average rates for the

1998 and 1999 surveys are presented in table 1 and are

the main reference for the rest of the discussion in this

section. In addition to smoothing out any seasonal

component, these 2-year averages are less affected by

sampling variability, which can be problematic for

some of the smaller subpopulations for which prevalence rates are reported.

Prevalence of Children’s Hunger, by

Household Characteristics

Single-parent families, and especially single-mother

families, are at higher risk of children’s hunger than

are two-parent families. The prevalence of children’s

hunger was six times as high in single-mother families

as in two-parent families (1.8 percent compared with 0.3

percent). Single-mother families comprised 23 percent

of all households with children, but accounted for 57

percent of households with hunger among children.

The prevalence of hunger among children was also

above the national average in single-father families

(0.9 percent), although this rate was only half that of

single-mother families.

Children’s hunger is nearly three times more prevalent

among racial and ethnic minorities than among the

majority population. Children were hungry at times

during the year in 1.3 percent of Black households

and 1.4 percent of Hispanic households, compared

with 0.5 percent of White non-Hispanic households.

These differences are associated primarily with the

lower incomes and higher poverty rates of minority

households.

Hunger, as measured by the CPS Food Security

Survey, is specifically “resource constrained” hunger.

Every question in the scale specifies lack of money to

buy food as the reason for the experience or condition.

Hunger is expected, therefore, to be strongly associated

with income, and this is, indeed, the case. Children’s

hunger was about 10 times as prevalent among households with incomes below 185 percent of the official

poverty line as for those with incomes above that line.

In households below this income threshold, children

are eligible for reduced-cost meals under the USDA

School Lunch and School Breakfast Programs; infants,

young children, and pregnant or breast-feeding mothers are eligible for WIC supplemental foods; and

children’s meals in the Child and Adult Care Food

Program are reimbursed at higher levels.4 At still lower

levels of income, hunger was yet more prevalent; 2.5

percent of households with annual incomes below the

official poverty line reported that children were hungry

at times during the year, compared with 0.2 percent of

households with incomes above 185 percent of the

poverty line. 

Rural and urban areas reported similar prevalence rates

of children’s hunger overall (0.7 percent), although the

rate in central cities of metropolitan areas was somewhat higher (1.0 percent). The prevalence of hunger

might be expected to be higher in nonmetropolitan

than in metropolitan areas because the poverty rate is

higher in nonmetropolitan areas. However, the metropolitan-nonmetropolitan pattern of children’s hunger is

consistent with that for food insecurity and hunger of

all households (Andrews et al., 2000; Bickel, Carlson,

and Nord, 1999). Lower costs of living in rural areas

probably account for part of this hunger/poverty 

disjuncture. Poverty calculations do not take cost-ofliving differences among areas into account while

measures of food insecurity and hunger directly gauge

the severity of food deprivation resulting from lack of

purchasing power. If living costs, on the whole, are

lower in rural areas, even a poverty level income

could stretch farther there, resulting in less food 

deprivation than in urban areas.

How Many Children Were Hungry?

Larger families are somewhat more vulnerable to

hunger than smaller families, so the proportion of the

Nation’s children who live in households with children’s

hunger is slightly higher than the proportion of households with children’s hunger. On average in 1998 and

1999, some 613,000 children (0.9 percent of all children) lived in the 275,000 households (0.7 percent of all

households with children) where children’s hunger

occurred (table 2).

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  5

4 The Special Supplemental Nutrition Program for Women,

Infants, and Children (WIC) provides targeted supplementary

foods in conjunction with health care to women during and after

pregnancy, to infants, and to children through age 4.
However, as noted earlier, not every child in households reporting children’s hunger experienced this

resource-constrained hunger. The CPS Food Security

Survey does not ask about the experience of each child

separately, but rather whether any child in the household experienced various forms of food deprivation. In

some households classified as having hunger among

children, only the older children were hungry, while

younger children were protected from hunger. Thus,

the number of children living in households with

children’s hunger (613,000) provides an upper bound

estimate of the actual number of hungry children in

the Nation in this period. A lower-bound estimate is

provided by the number of households with hungry

children during the year (average 275,000 in 1998-

99), since at least 1 child was hungry within each of

these households.

Trends in the Prevalence of Children’s

Hunger, 1995-99

The prevalence rate of children’s hunger declined substantially from 1995, when household food security

and hunger were first measured nationally in the

6  Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25 Economic Research Service/USDA

Table 2—Children in households with hunger among children, 1998 and 1999

Total children in all households Children in households with children’s hunger1

Household characteristics 1998 1999 Average 1998 1999 Average 1998 1999 Average

------------------------------------------------------------------------1,000----------------------------------------------------------- --------------------Percent---------------------

All children 71,282 71,418 71,350 716 511 613 1.0 0.7 0.9

Household structure:

Married-couple families 50,688 50,819 50,753 250 203 226 .5 .4 .4

Female head, no spouse 16,012 16,134 16,073 395 261 328 2.5 1.6 2.0

Male head, no spouse 3,452 3,526 3,489 52 29 41 1.5 0.8 1.2

Other households with child2 1,130 939 1,035 19 18 19 1.6 2.0 1.8

Race and ethnicity:3

White non-Hispanic 46,515 45,934 46,224 256 191 223 .5 .4 .5

Black non-Hispanic 10,753 10,733 10,743 231 111 171 2.1 1.0 1.6

Hispanic4 10,685 11,485 11,085 193 147 170 1.8 1.3 1.5

Other non-Hispanic 3,329 3,266 3,298 36 63 50 1.1 1.9 1.5

Household income-to-poverty ratio:

Under 1.00 13,801 13,301 13,551 416 297 357 3.0 2.2 2.6

Under 1.30 (includes under 1.00) 18,481 17,475 17,978 547 342 445 3.0 2.0 2.5

Under 1.855 (includes under 1.30) 27,381 25,840 26,610 621 429 525 2.3 1.7 2.0

1.85 and over5 38,950 40,472 39,711 80 73 76 .2 .2 .2

Area of residence:

Inside metropolitan area 57,452 57,735 57,593 576 434 505 1.0 .8 .9

In central city6 17,552 17,231 17,392 249 148 198 1.4 .9 1.1

Not in central city6 30,190 31,002 30,596 281 238 260 .9 .8 .8

Outside metropolitan area 13,831 13,683 13,757 140 77 108 1.0 .6 .8

1Not all children were hungry in some households with hunger among children.

2Households with children in complex living arrangements, e.g., children of other relatives or of unrelated roommate or boarder.

3Race/ethnicity of household reference person.

4Hispanics may be of any race.

5Subtotals do not add to national total because income is not reported for 8.7 percent of households.

6Subtotals do not add to metropolitan area total because central city residence is not identified for some households.

Source: Calculated by ERS from Current Population Survey Food Security Supplement data, August 1998 and April 1999, based on the children’s food 

security scale.
United States, to 1999 (fig. 1). Overall the prevalence

of children’s hunger declined by about half, from 1.1

percent of all households with children in 1995 to 0.6

percent in 1999.5

The fall in hunger prevalence among children extended

to all major demographic and income categories,

including those most vulnerable to hunger. The prevalence rate of children’s hunger among single-mother

families declined from 2.7 percent in 1995 to 1.4 percent in 1999. Even among low-income households, the

prevalence of children’s hunger declined by almost

half from 3.1 percent in 1995 to 1.7 percent in 1999.

The decline for two-parent families was similar in

proportion, although the percentage-point decline was

much smaller (0.5 percent in 1995 to 0.3 percent in

1999). Only in households with incomes above 130

percent of the poverty line was the prevalence of

hunger unchanged from 1995 to 1999, remaining at

about 0.3 percent.

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  7

5 To avoid bias in the trend analysis due to seasonal differences

in food insecurity, statistics from 1995 were compared with those

from 1999 only, rather than to the 1998-99 averages. The food

security survey was conducted in April in both 1995 and 1999.

Data in figure 1 were not adjusted for inter-year differences in

screening (Andrews et al., 2000; Bickel et al., 1999). These adjustments have a negligible effect on estimates of children’s hunger

because very few households with levels of deprivation this severe

were affected by the screening protocol used in any year. In 1999,

for example, the estimated prevalence of children’s hunger based

on the data as collected (the “full information” or “maximum sample” estimate presented in figure 1) was 0.58 percent, while the

estimate for 1999 based on the common screen for strict comparability across all years 1995-99 was 0.55 percent.

Source: Calculated by ERS based on data from Current Population Survey Food Security Supplements 1995-99.

Figure 1

Prevalence of children's hunger, 1995-99

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

1995 1996 1997 1998 1999

Prevalence rate---percent of households1

Below 130% poverty

Single-mother family

All households with child

Single-father family

Two-parent family

Above 130% poverty

1Households without children were excluded from the denominators.
Children in Food-Insecure Households

Children may be adversely affected by less severe levels of personal and household food deprivation than

the range in which the children themselves experience

resource-constrained hunger (Cook et al., 2001). A

more comprehensive picture of children’s food security status is provided by combining information from

the household food security scale and the children’s

food security scale.6 Households with hunger among

children are a subset of households with hunger

among adults, which, in turn, are a subset of foodinsecure households.

A tabulation of households with children by these

combined measures of food security is presented in

table 3. In 1998, 82.4 percent of households with

children were food secure, 13.3 percent were food

insecure without hunger, 3.5 percent were food insecure with hunger among adults, but not children, and

0.9 percent were food insecure with hunger among

both adults and children. In 1999, the corresponding

percentages were 85.2 percent food secure, 11.5 percent food insecure without hunger, 2.7 percent food

insecure with hunger among adults, but not children,

and 0.6 percent food insecure with hunger among

both adults and children.7

8  Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25 Economic Research Service/USDA

6 An alternative approach, discussed in more detail in chapter 2,

is to specify a less severe threshold on the children’s food security

scale and classify households vis-à-vis that threshold as well as the

children’s hunger threshold.

7 A fourth category is logically possible, “food insecure with

hunger among children but not adults.” In data analyzed to date, no

households were found in this category provided that the full 18-

item scale is used to identify households with hunger among adults.

However, if only the 10 adult and household items are used to identify hunger among adults (using the scale that is normally applied

to households without children), then a small proportion of households are classified as having hunger among children but not

among adults.

It should be noted that this tabulation combines information

from two scales and does not represent a single underlying continuous scale of severity combining household-level and child-specific

items. No such scale can adequately represent both household and

child-specific food insecurity because these two phenomena, while

closely related, lie on slightly different dimensions. See chapter 3

for a full discussion of the bidimensionality in the 18-item set.

Table 3—Food security and hunger status of households with children, 1998 and 1999

Food insecure

With hunger With hunger 

among among

adults, but adults and

Household characteristics Total Food secure Without hunger not children children

1,000 1,000 Percent 1,000 Percent 1,000 Percent 1,000 Percent

Panel A: Households with children, 1998

All households with children 38,036 31,335 82.4 5,049 13.3 1,321 3.5 331 0.9

Married-couple families 26,306 23,284 88.5 2,468 9.4 449 1.7 105 .4

Female head, no spouse 8,807 5,692 64.6 2,183 24.8 739 8.4 193 2.2

Male head, no spouse 2,153 1,727 80.2 308 14.3 98 4.6 20 .9

Other households with child1 770 632 82.1 89 11.6 35 4.5 14 1.8

Household income < 130% poverty 8,162 4,556 55.8 2,581 31.6 787 9.6 238 2.9

Panel B: Households with children, 1999

All households with children 37,884 32,290 85.2 4,340 11.5 1,035 2.7 219 0.6

Married-couple families 26,303 23,771 90.4 2,105 8.0 353 1.3 75 .3

Female head, no spouse 8,744 6,146 70.3 1,890 21.6 586 6.7 123 1.4

Male head, no spouse 2,187 1,817 83.1 280 12.8 72 3.3 17 .8

Other households with child1 650 556 85.6 66 10.1 25 3.8 3 .5

Household income < 130% poverty 7,583 4,525 59.7 2,278 30.0 651 8.6 129 1.7

1Households with children in complex living arrangements, e.g., children of other relatives or of unrelated roommate or boarder.

Source: Calculated by ERS from Current Population Survey Food Security Supplement data, August 1998 and April 1999.
The 18 items in the household food security scale

include:

z 3 items that ask about experiences of the entire

household

z 7 items that ask about experiences and behaviors of

the adult members of the household as a group, or

of the adult respondent individually

z 8 items that ask about experiences and conditions of

the children in the household as a group.

The eight child-referenced items are used to calculate

the children’s food security scale, a graduated, continuous measure of the severity of food insecurity among

children in the household. The scale provides the

framework for a corresponding categorical measure of

households with children’s hunger. This latter measure

classifies households as to whether or not the severity

of food deprivation reported over the previous 12

months gives clear evidence of hunger among the

children in the household. We begin this chapter with

a conceptual description of the children’s food security

scale and of the categorical threshold that identifies

households with children’s hunger. We then describe

statistical assessments of the scale items and of the

overall reliability of the scale. The conceptual description is intended to be accessible to all interested

readers. The description of the statistical model and

its applications is somewhat technical and a moderate

level of statistical knowledge is required to understand

that section. Detailed information on implementing

the children’s food security scale is presented in

appendix B.

Conceptual Basis of the Children’s 

Food Security Scale

An essential characteristic of both the household food

security scale and the children’s food security scale is

that the items comprising them vary across a wide

range of severity of food insecurity. The precise

severity level of each item (the “item calibration,”

discussed below) is estimated empirically from the

overall pattern of response to the scale items by U.S.

households. However, the range of severity of the

conditions identified by the items is also intuitively

evident from inspection of the items. In the children’s

food security scale, for example, the item, children

not eating for a whole day, is a more severe manifestation of food insecurity than is the item, cutting the

size of children’s meals, and the latter indicates a

more severe level of food insecurity than does the

item, relied on a few kinds of low-cost food to feed

the children. These differences in severity are

observed in the response patterns of surveyed households. The more severe items are less frequently

affirmed than less severe items. Moreover, a household that affirms an item of midrange severity is

likely to have also affirmed all items that are less

severe. Similarly, a household that denies an item at

midrange is likely to deny all items that are more

severe. These typical response patterns are not universal, but they are predominant. And among

households that do deviate from the typical patterns,

the extent of deviation tends to be slight.

This highly regular pattern of severity ordering of the

food security indicator items is the basis of the statistical model used to calculate and assess the food security

scales. The statistical model expresses and summarizes

in succinct quantitative form the consistently ordered

pattern that exists in the U.S. population of the diverse

conditions, experiences, and behavioral responses that

identify, and to some extent constitute, the phenomenon

of food insecurity.8 This underlying ordering of the

items measuring food insecurity through successive

levels of severity also provides a framework for relating

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  9

Chapter 2

The Children’s Food Security Scale

8 While the indicator items are diverse in nature, reflecting the

inherent multidimensionality of the phenomenon of food insecurity, the highly ordered response pattern among the items reveals an

underlying unifying dimension as well—the severity of the phenomenon, as experienced by the surveyed households. This

empirical property—the ordered character of the responses—

enables the response data to be fitted to unidimensional scale

measures of severity both at the household and child-specific

levels. The importance of these unidimensional severity scales is,

first, that they represent a higher order of measurement than simple

categorical or ordered measures, and second, that they provide a

methodologically sound basis for estimating the prevalence of

specified ranges of severity of food insecurity.
the total number of items affirmed by a household (the

household’s “raw score”) to the conditions existing

within the household. For example, households with a

raw score of 5 can be characterized as having affirmed

the five least severe items and having denied the

remaining three more severe items. We can draw on

this property of the item set to select an appropriate

threshold, in terms of household raw score, to identify

households with children’s hunger. Table 4 lists the 18

items in the household food security scale, ordered by

severity as measured in 1998. The item calibration

(described in more detail later in this chapter) is a

measure of the severity of each item as inferred statistically from the pattern of responses of all households

to all items.

The items in the children’s food security scale are

particularly strongly ordered. In 1995, among households that affirmed at least one item but not all items,

78 percent conformed exactly to the most typical, or 

modal, pattern described above.9 That is, these

“modal households” affirmed one or more items,

beginning with the least severe and continuing in

order of increasing severity until, beginning at some

particular level of severity for each household,

they then denied all of the more severe items.

Furthermore, among all households with children,

few of the responses that were not perfectly ordered

departed very far from this characteristic pattern.

Identifying Households with Children’s

Hunger—The Categorical Measure

The strong ordering of the indicator items justifies using

the household raw scores to identify households with

children’s hunger. We set the threshold for identifying

10  Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25 Economic Research Service/USDA

Table 4–Item calibrations based on August 1998 Current Population Survey Food Security Supplement data

Reference Item description Item calibration1

Household Worried food would run out 1.488

Household Food bought didn’t last 2.793

Food-insecurity threshold on household scale

Child Relied on a few kinds of low-cost food for children 3.268

Household Couldn’t afford to eat balanced meals 3.669

Child Couldn’t feed the children a balanced meal 5.040

Adult Adult cut size of meals or skipped meals 5.374

Adult/respondent Respondent ate less than felt he or she should 5.534

Hunger threshold on household scale (identifies households with hunger among adults)

Adult Adult cut or skipped meals, 3 or more months 6.424

Child Children were not eating enough 6.661

Adult/respondent Respondent hungry but didn’t eat 7.545

Adult/respondent Respondent lost weight 8.613

Child Cut size of child’s meals 8.791

Severe hunger threshold on household scale; children’s hunger threshold on children’s food security scale

Adult Adult did not eat for whole day 9.122

Child Child hungry but couldn’t afford more food 9.240

Adult Adult did not eat for whole day, 3 or more months 9.934

Child Child skipped meal 9.935

Child Child skipped meals, 3 or more months 10.627

Child Child did not eat for whole day 11.944

1 Calibrations are based on the standard computational metric (i.e., with discrimination parameter of 1 and mean item calibration of 7; see Bickel et al., 2000).

Source: Calculated by ERS based on August 1998 Current Population Survey Food Security Supplement data.

9 Data from 1995 were used for this assessment of modality

because the 1998 and 1999 questionnaires included internal

screens to reduce respondent burden that also had the effect of

artificially suppressing highly nonmodal responses. 
children’s hunger at a raw score of five items affirmed.

Thus, a household just below this threshold level of

severity—almost, but not quite, severe enough to be

classified as having hunger among children—will have

affirmed four items, typically the four least severe items.

That is, the household will report that:

z They often or sometimes relied on only a few kinds

of low-cost food to feed the children because they

were running out of money to buy food.

z They often or sometimes couldn’t feed the children

a balanced meal because they couldn’t afford that.

z The children were not eating enough because they

just couldn’t afford enough food.

z They cut the size of the children’s meals because

there wasn’t enough money for food.

A typical household just beyond the threshold—just

severe enough to be classified as having hunger among

children—will have affirmed those same four items,

and in addition will have reported that:

z The children were hungry but they just couldn’t

afford more food.

This last item may be described as the “threshold

item” for the range of severity on the measurement

scale that corresponds to the category, “food insecure

with children’s hunger.” The subsequent items within

that range, children skipping meals and children not

eating for a whole day, are measurably more severe as

indicators of children’s hunger than the threshold item.

Thus, all of the households classified by this method

as having children’s hunger will have affirmed one or

more child-hunger items that are at least as severe as

the threshold item. A small proportion (around onefourth) of the borderline households—those whose

response pattern places them just within the children’s

hunger category—will have denied the threshold item

and instead will have affirmed an item that is more

severe than the threshold item.

In the original work to develop the U.S. household

food security scale, Hamilton et al. (1997a) made the

first effort to identify households with hunger among

children by defining a “severe hunger” category on the

18-item household scale. This household-level severehunger category was developed by first identifying the

range of severity of children’s hunger in households

with children, establishing the same line of reasoning

that is followed in the current study. That is, a “shadow” threshold for children’s hunger was first identified

in the sequence of child-referenced items, as these

were combined with the household- and adult-referenced items in the 18-item scale. The “shadow”

threshold item was The children were hungry but we

just couldn’t afford more food, which is the same item

we have identified as the threshold for the children’s

hunger range. Then, since an objective of the household scale was that it be consistently applied across all

households—both with and without children—the

adult-referenced item most nearly corresponding in

severity to the “shadow” threshold was designated as

the household-level threshold indicator defining the

severe-hunger range, or severe-hunger category, for all

household types. The threshold item selected was

Adult did not eat for whole day.

With regard to the child-referenced items, the original

severe-hunger threshold corresponds exactly to the

children’s hunger threshold specified in the current

report. However, even though the thresholds are the

same in the two scales, the children’s food security

scale identifies a substantially larger number of households with hungry children. In chapter 3, we discuss

the reasons for this difference in prevalence estimates

and classification between the severe-hunger category

on the household scale and the children’s hunger category on the children’s food security scale.

Not only is the children’s hunger threshold specified in

this report consistent with the corresponding severehunger threshold in the household-level scale, it also is

conceptually consistent with the operational principles

developed in setting the household-level hunger

threshold on the 18-item scale—in effect, the corresponding adult-hunger threshold. The operational rule

of thumb that emerged in the development of the original scale and its associated categorical measure

(Hamilton et al., 1997a, 1997b) required that a household affirm multiple indicators of reduced food intake

to be classified “food insecure with hunger.” This

extent of reduced food intake and disruption of eating

patterns indicates the likelihood of the direct experience of hunger—i.e., “the uneasy or painful sensation

caused by a lack of food” (Anderson, 1990, following

the Oxford English Dictionary). This is a methodologically conservative decision rule, designed to minimize

false-positive classifications. Similarly, to pass the

children’s hunger threshold, at least three indicators of

reduced food intake among children are required: the

children were not eating enough, the size of children’s

meals was cut, and the children were hungry.

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  11
It is important to keep this methodological conservatism in mind when interpreting statistics from either

the children’s food security scale or the householdlevel food security scale. Although households beyond

the respective thresholds can be labeled quite confidently as “food insecure,” or “food insecure with

hunger,” or “food insecure with hunger among children,” households with scores just below the

thresholds cannot be described with as much confidence as “food secure,” or “not having hunger,” or “not

having hunger among children.” For example, some

proportion of the households classified as not having

hunger among children do, in fact, affirm one or two

items indicating reduced food intake among children

due to constrained household resources. In 1998, just

under 1 percent of households were classified as food

insecure with hunger among children. An additional

4.6 percent of households affirmed one or more items

indicating reduced food intake among children. In

some of these households, children may have been

hungry at times because the family lacked money to

buy food, yet these households are classified as not

having hunger among children.

There are several detailed respects in which the childhunger threshold is not precisely parallel to the

adult-hunger threshold, due in each case to slight differences between the adult- and child-hunger indicator

items available in the CPS food security data. One of

these is that the third indicator of reduced food intake

among adults—the threshold item for adult hunger—is

an item indicating a repeated pattern of reduced food

intake in 3 or more of the past 12 months. This represents an additional, temporal dimension indicative of

increased severity of food insecurity. It also reflects a

secondary formal conceptual definition of hunger presented in the 1990 Life Sciences Research Office

report: “The recurrent and involuntary lack of access

to food” (Anderson, 1990). A strictly parallel procedure in identifying the children’s hunger threshold was

not possible given the available data. Among the childspecific items, frequency information was collected

only for the “skipped meals” question, which is

comparatively a more severe indicator item than the

threshold item for adult hunger, cutting the size of

meals or skipping meals in 3 or more months.10 In

another sense, the children’s hunger threshold might

be viewed as relatively more severe than the adult

threshold in that the children’s hunger threshold item

explicitly affirms that children were hungry, whereas

the adult hunger threshold does not require this explicit

affirmation for adults.

The discussion of the children’s hunger threshold has,

to this point, focused primarily on households located

just beyond the threshold, those that affirmed exactly

five items. However, most of the households classified

as having children’s hunger affirmed more than five

items, indicating that they had experienced still higher

levels of food stress. The distribution of response patterns of the households classified as having children’s

hunger provides a more accurate picture of the conditions and experiences of children in these households

(table 5). Almost all households classified as having

hunger among children affirmed the three least severe

scale items. Nearly 83 percent affirmed the item that

asked directly about whether children were hungry; 71

percent reported that children skipped meals because

there wasn’t enough money for food; and in one-fifth

of the households with children’s hunger, children

went a whole day without eating.

Identifying a Less Severe Threshold of

Food Insecurity Among Children

Children may be adversely affected by levels of food

insecurity that are less severe than the hunger level

(Cook et al., 2001), and may also be affected indirectly

by food insecurity and hunger experienced by adults in

the household. In an earlier paper (Nord and Bickel,

1999), we specified experimentally a less severe

threshold on the children’s food security scale that

identified households in which the quality and variety

of children’s diets were reduced. Households that

affirmed two or more of the child-referenced items—

typically that they relied on a few kinds of low-cost

food for the children and that they couldn’t feed the

children a balanced meal—were classified in that

paper as having “reduced quality and variety of children’s diet.” Based on that threshold, 8.9 percent of

households with children would be assigned to the

category of reduced quality and variety of children’s

diets in 1998-99. We have not presented detailed 

statistics based on that threshold in the current report

because there is as yet no expert consensus on whether

such a boundary represents a meaningful increment in

severity of children’s food insecurity, and if it does,

what language should be used to describe it. For 

example, it is not clear that the nutritional quality of

12  Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25 Economic Research Service/USDA

10 The item that asks about adult hunger also differs from the

parallel child item in being referenced only to the respondent, not

to “you or other adults in the household.”
children’s diets is necessarily or significantly reduced

beyond that particular threshold. More research and

discussion are needed to establish a threshold that 

adequately represents a meaningful range of severity

of food stress among children.11

An alternative approach, used in chapter 1 of this

report, is to combine information from the household

food security scale with information from the children’s

food security scale to provide a more comprehensive

representation of the entire range of food stress and

food deprivation in households with children.

Households with hunger among children are a subset of

households with hunger among adults, just as the latter

are a subset of all food-insecure households.12 Thus,

combining the two scales provides a four-level categorical measure: food secure, food insecure without

hunger, food insecure with hunger among adults but

not children, and food insecure with hunger among

both adults and children. 

It is important to note, however, that this tabulation

does not represent or reflect a single underlying

continuous scale combining household-level and

child-specific items. No such scale can adequately

represent both household and child-specific food insecurity because these two aspects, while closely

related, lie on slightly different dimensions of the

general phenomenon. See chapter 3 for a full discussion of the bidimensionality in the 18-item set.

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  13

Table 5–Proportion of households that affirmed child-referenced items, average 1998-99

In households

In all households with hunger

Item with children among children

Percent

Relied on a few kinds of low-cost food for children 15.4 98.8

Couldn’t feed the children a balanced meal 8.9 96.0

Children were not eating enough 4.8 91.0

Cut size of child’s meals 1.3 78.1

Child hungry but couldn’t afford more food 1.0 82.8

Child skipped meal 0.7 70.8

Child skipped meals, 3 or more months .5 58.4

Child did not eat for whole day .2 20.2

Affirmed no items, or were screened out 83.5 0

Affirmed 1 item 7.6 0

Affirmed 2 items 4.2 0

Affirmed 3 items 3.2 0

Affirmed 4 items .7 0

Affirmed 5 items .3 43.8

Affirmed 6 items .2 24.8

Affirmed 7 items .2 24.1

Affirmed 8 items .1 7.3

Note: Prevalences are based on household supplement weights to represent the national population.

Source: Calculated by ERS based on August 1998 and April 1999 Current Population Survey Food Security Supplement data.

11 The thresholds, or severity-range boundaries, specified with

respect to the household food security scale were set, and language

was selected to describe the resulting categories, by a team of

experts on nutrition and food behavior (Carlson et al., 1999). These

thresholds are necessary to create the categorical form of the food

security measure (i.e., food secure, food insecure without hunger,

food insecure with hunger) needed for monitoring changes in the

prevalence of food insecurity and hunger. For this monitoring use,

the designated categorical ranges are meaningful in their own

right. However, whether these identifiable ranges of severity in the

underlying phenomenon provide meaningful indicators for variation in the nutritional and health consequences of food stress and

food deprivation is not yet known.

12 It is logically possible for a household to register hunger

among children but not among adults, but in the data sets examined to date—including 6 CPS Food Security Supplements and 3

other nationally representative data sets—no instance of this has

been observed, provided that the full 18-item scale is used to identify households with hunger among adults. However, if only the 10

adult and household items are used to identify hunger among

adults (using the scale that is normally applied to households without children), then a small proportion of households are classified

as having hunger among children but not among adults.
Rasch Measurement Model: 

Basic Concepts

The 18-item household food security scale was developed through the use of Rasch modeling methods,

and we used the same methods to create the 8-item

children’s food security scale. The Rasch measurement

model provides powerful analytic tools to assess the

suitability of a set of items for scale construction. We

used it to assess the scalability of the child-referenced

items and to assess the stability and reliability of the

children’s food security scale. In essence, the Rasch

model formalizes the concept of the severity-ordering

of items as discussed above and provides standard 

statistical measures of the extent to which the response

patterns observed in a data set are consistent with this

concept. A basic understanding of the Rasch statistical

model will help to clarify the meaning of item severity

and of other statistics used to assess the children’s

food security scale and the items that comprise it.

The Rasch model was developed primarily in the educational testing field, where multiple correct/incorrect

items, varying in difficulty, are used to measure an

individual’s level of knowledge or skill. More generally, the model can be used to assess the location of an

individual or household along a continuum—in the

current case, a continuum of the severity of deprivation

in the basic need for food—by combining information

from multiple dichotomous (yes/no) items that vary as

to the point on the continuum that each one uniquely

reflects. This corresponds exactly to the character of

the food insecurity/hunger measurement construct.

There is no commonly used language that describes

the entire continuum of food insecurity and hunger.

People do not ask, “On a scale of 1 to 10, how food

insecure is your household?” But people do speak

readily about specific experiences, such as running out

of money for food, and the specific behaviors and conditions that result, such as being forced to cut back on

quality or quantity of food. Information about these

experiences, behaviors, and conditions then, can be

elicited by well-designed survey questions. 

The food security scale works well as a measure

because the behaviors and experiences represented by

the 18 items in the scale correspond closely to the

most prevalent experiences and responses of the U.S.

population in coping with inadequate resources for

food. This result was achieved by basing the questions

upon a substantial body of research among lowincome U.S. families regarding their experiences of

food deprivation and how they described and coped

with them. (Wehler et al., 1992; Radimer et al., 1990;

Radimer et al., 1992; Fitchen, 1981; Fitchen, 1988).

The questions reflect familiar conditions, experiences,

and behaviors, and use natural language derived from

the qualitative research to describe them. This set of

conditions, experiences, and behaviors reflects the

range of variation in severity across the continuum of

food insecurity and hunger, just as the set of questions

in a well-designed test vary in difficulty across an

appropriate range in order to reflect accurately the

level of knowledge of the test-taker.

Using the Rasch model to create a measure of food

insecurity and hunger assumes that both the indicator

items making up the scale and the households responding to the items can be located on the same underlying

continuum of severity of food insecurity. It further

assumes that the probability of a specific household

affirming a specific item depends on the difference

between the severity level of that household and the

severity of that item. The single-parameter Rasch

model, which is used to create the household food

security scale as well as the children’s food security

scale, assumes specifically that the log of the odds of a

household affirming an item is proportional to the difference between the “true” severity level of the

household and the “true” severity level of the item.

Thus, the odds that a household at severity level h will

affirm an item at severity level i is:

ph,i/qh,i=e(h-i)

where p is the probability of affirming the item, q is

1-p, that is, the probability the household will deny the

item, and e is the base of the natural logarithms. The

probability that the household will affirm the item is:

ph,i=e(h-i)/(1+e(h-i))

The severity of an item, then, can be thought of as the

severity level of households that are just at the threshold of affirming or denying that item. The odds that a

household will affirm an item right at the “true” severity level of the household is 1, corresponding to a

probability of 0.5. The odds that a household will

affirm an item with a severity score 1 unit lower than

that of the household is e1, or about 2.7, corresponding

to a probability of 0.73 [i.e., 2.7/(1+2.7)]. The probability that the household will affirm an item 2 units

lower than its own severity measure is 0.88, and for an

14  Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25 Economic Research Service/USDA
item 3 units lower, it is 0.95. Since it is the difference

between the household and item severity levels that

determines the probability of affirmation, it is clear

that the metric of the severity scale can be transformed

by adding a constant to both household and item

scores without changing the character of the scale.

That is, the size of the intervals on the scale conveys

meaningful information, but the zero point is arbitrary.

The Federal interagency food security measurement

project has adopted a standard computational metric

for the 18-item scale based on a mean item score of 7

for the 18 items in order to keep all item and household scores positive (Bickel et al., 2000). This results

in household scores that range from about 1.5 to 13.13

Software that implements the Rasch model begins with

the household-by-item matrix of responses. Maximumlikelihood methods are then used to estimate

simultaneously the household and item severity scores

most consistent with the observed responses under the

Rasch assumptions. The resulting household scores are

a continuous interval-level measure of the extent of

food insecurity or hunger in the households. These

scores are appropriate for associative analyses such as

correlation and regression, with the caveat that the

score for households that denied all items or were

screened out cannot be estimated by the Rasch model.

The score of zero assigned to such households in some

datasets is purely nominal. While Rasch modeling produces an interval scale, the size of the interval between

households that denied all items and those that

affirmed one item cannot be determined statistically.

The Rasch model also provides the basis for “fit” statistics that assess how well each item, each household,

and the overall data conform to the assumptions of the

measurement model. 

Severity of Items in the Children’s 

Food Security Scale

To create the continuous children’s food security scale,

responses to the eight child-referenced items by all

households with children were submitted to Rasch

modeling software without the adult-specific and

household items. The severity order of the eight childreferenced items when scaled without the adult and

household items was identical to their order in the allitems scale (table 6; fig. 2).14 This was expected, since

the calibrations of these items in both scales depend

only on the responses of households with children. The

relative severities of the eight items were also nearly

perfectly proportional in the two scales. The correlation of the item calibrations in the two scales in 1995

was 0.997. However, the range of severity of the items

was greater when they were scaled alone. This can be

seen in figure 2 and can be expressed statistically by

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  15

13 For some communication purposes, the Federal project further transforms the scale to a 0-10 metric by multiplying the scores

from the standard computational metric by 10/14. While the 0-10

scale is more intuitively accessible, researchers need to keep in

mind that the natural logistic interval length has been modified in

this transformation.

14 The metric of the child scale in figure 2 was adjusted by

adding a constant so that the mean of the calibrations of the 8

child items was equal to the mean of the same 8 items in the 18-

item scale.

Table 6—Calibration of items in the children’s food security scale1

1995 1998

Scaled with Child items Scaled with Child items 

Item all 18 Items scaled alone all 18 items scaled alone

Relied on a few kinds of low-cost food for children 3.92 1.36 3.27 -.23

Couldn’t feed the children a balanced meal 5.35 3.95 5.04 3.49

Children were not eating enough 6.78 6.32 6.66 6.43

Cut size of child’s meals 8.59 8.95 8.79 9.39

Child hungry but couldn’t afford more food 8.86 9.33 9.24 9.99

Child skipped meal 9.97 10.87 9.94 10.93

Child skipped meals, 3 or more months 10.57 11.70 10.63 11.87

Child did not eat for whole day 12.01 13.58 11.94 13.65

Mean 8.26 8.26 8.19 8.19

Standard deviation 2.56 3.85 2.76 4.35

1Calibrations were calculated under Rasch-model assumptions using joint maximum likelihood methods. The discrimination parameter was set at unity, and

mean item score was set at the mean of the eight child items in the standard scale as described in Bickel and Nord (2000).

Source: Calculated by ERS based on April 1995 and August 1998 Current Population Survey Food Security Supplement data.
16  Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25 Economic Research Service/USDA

Figure 2

Item calibration (severity) of child-referenced items scaled alone compared with calibration when scaled with all 18 items

0

2

4

6

8

10

12

14

0 2 4 6 8 10 12 14

Item calibration—scaled with all 18 items

Source: Calculated by ERS based on data from Current Population Survey Food Security Supplements 1995-1999.

Item calibration—child items scaled alone

Child item

Equal score

Regression (r=0.997)

Child skipped meals, 3 or more months

Child did not eat for whole day

Child hungry

Child skipped meal

Cut size of child's meals

Children were not eating enough

Couldn't feed children a balanced meal

Relied on few kinds of low-cost food for children

Figure 3

Item scores of child items scaled with all 18 items, by year

Source: Calculated by ERS based on data from Current Population Survey Food Security Supplements 1995-1999.

2.0

4.0

6.0

8.0

10.0

12.0

14.0

1995 1996 1997 1998 1999

Year

Item score

Child did not eat for whole day

Child skipped meals, 3+ months

Child skipped meal

Child hungry

Cut size of child's meals

Children were not eating enough

Couldn't feed children a balanced meal

Relied on few kinds of low-cost food

for children
comparing the standard deviation of the items in the

two scales. In 1995, the standard deviation of the

child-specific items when scaled with all 18 items was

2.56. When scaled alone, the standard deviation of the

same items was about 50 percent greater at 3.85. A

similar pattern is seen in 1998. This greater range indicates a more consistent ordering of the child items

when they are scaled alone, which translates statistically to higher “discrimination”—i.e., sensitivity—of the

items. This is a result of the greater homogeneity of

these items as a set compared with the modest bidimensionality (i.e., an adult hunger dimension and a

children’s hunger dimension) present in the 18-item

set. This slight bidimensionality is, in fact, the reason

the severe hunger category of the household scale does

not perform well in identifying households with

hunger among their child members. We explore this

issue further in chapter 3.

The children’s food security scale was highly stable

from year to year. The severity-order of the items was

invariant across years and relative item severities were

quite consistent (fig. 3). The stability of the measurement construct over time increases confidence in the

stable relationship of the items to the underlying phenomenon of food insecurity and validates cross-year

comparisons of prevalence estimates based on the scale.

The greater item range in 1998 and 1999 as compared

with earlier years probably resulted largely or entirely

from a change in the questionnaire structure of the CPS

Food Security Survey and in the screening procedures

followed during survey administration. Beginning in

1998, items were administered in approximate order of

severity. Households that did not affirm any item in the

least severe block (five items for households with children) were skipped over the remaining items and

deemed to have denied them. A second, similar screener

was inserted after an additional six items. This screening

protocol reduces respondent burden and avoids the awkwardness of asking questions that are inappropriate in

light of earlier responses. However, screening out a

small proportion of highly atypical response patterns

that would otherwise be observed also improves the fit

of items to Rasch model assumptions.15

The Children’s Food Security Scale: A

Graduated Measure of Food Deprivation

Among Children

The categorical measure of hunger among children

described earlier in this chapter is appropriate for calculating prevalence rates of children’s hunger and for

some analytic purposes. However, a continuous,

interval-level measure providing more precise information about the level of severity of food deprivation

among children in households is desirable for many

associative analyses (correlation, regression, etc.) of

the causes and consequences of food deprivation

among children. The children’s food security scale—

the household severity score derived from fitting the

Rasch model to the child-specific items—provides

this more detailed and precise measure of food insecurity among children.

A characteristic of the single-parameter Rasch model

is that, for households with no missing items, each raw

score corresponds to a unique household severity

score, irrespective of which items are affirmed to

achieve the raw score. The advantage of using the

Rasch scores rather than raw scores is that the Raschbased scores are linear with respect to the underlying

phenomenon of food insecurity, while the raw scores

are not. As such, the Rasch-based scores are more

appropriate for use in linear models such as correlation

and regression analyses.

It is desirable to put the children’s food security scale

on the same metric, or unit of measure, as used in the

household food security scale. We accomplished this

by “anchoring” the item calibrations at their values

from the 18-item scale and calculating household

scores based on these fixed item scores.16 This assures

maximum comparability of the two scales and eliminates the need for a separate set of item calibrations

for the children’s food security scale. It introduces no

distortion into the children’s food security scale, since

the relative item severities of the child items were

found to be the same whether they were scaled with or

without the adult and household items. Household

scale scores and categorical assignments from the

children’s food security scale based on data from the

1998 national CPS Food Security Survey are presented

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  17

15 The patterns that are screened out are both improbable statistically and highly unlikely given what we know about households’

normal patterns of behavioral responses to food insecurity.

However, it is not known to what extent these are data or survey

errors in the form of miscoding by the interviewer or incorrect

responses due to misunderstanding or inattention by the respondent, and to what extent they represent actual, but highly unusual,

circumstances.

16 For this calculation, we set the item discrimination at the

ratio of the standard deviations of the items in the two scales to

reflect the higher discrimination of the child-referenced items

taken alone.
in table 7. We selected 1998 data because the core

food security module recommended by the Guide to

Measuring Household Food Security, Revised 2000

incorporates the item order and screening first introduced to the national CPS Food Security Survey in

1998, and the household food security scale scores

provided by the Guide are also based on the 1998 data.

Technically, table 7 is only applicable for households

that provide valid responses to all items in the child

hunger scale. For households that have missing

responses for one or more items, the scale score

depends on the number of items affirmed and on

which items were omitted. In practice, missing

responses to items in the core food security module are

rare, so this limitation has slight importance. Further,

in most surveys, (including the national CPS Food

Security Survey), missing items can be imputed based

on valid responses to other items (appendix B), raw

scores can be recalculated based on these imputed

responses, and household scores can then be assigned

from table 7. Thus, for most surveys, the standard

methods described in appendix B can be used to assign

food security scale scores and status categories, and no

Rasch modeling software is required. 

Statistical Assessment of the 

Children’s Food Security Scale

Two statistics commonly used to assess how well

responses to items correspond to the Rasch-model

assumptions (or “fit” the model) are “infit” and “outfit.”

After item calibrations and household scores have been

estimated, the probability of an affirmative response in

each cell of the household-by-item matrix is calculated.

The infit and outfit statistics are then calculated by

comparing the actual responses to the probabilistically

expected responses in each cell of the matrix. Infit is

an “information weighted” fit statistic for each item

that is sensitive to general item fit within the range

near the severity level of the particular item. (See

appendix A for further information about Rasch model

fit statistics.) Outfit is sensitive to unexpected responses

from households with severities much higher or lower

than that of the item—that is, to highly improbable

responses (outliers). Both statistics compare observed

deviations of responses from those expected under

Rasch assumptions, so the expected value of the statistics is 1. The single-parameter Rasch model, which is

used in creating the food security scales, assumes that

all items discriminate equally sharply, so fit-statistic

values (especially infit) that are far from unity call into

question the suitability of the item for use in the

scale.17

18  Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25 Economic Research Service/USDA

Table 7—Household scores on the children’s food security scale

Scale score

Standard

computational Standard

Number of items affirmed (raw score) metric 0-10 metric Children’s hunger status 

0 items (or screened out) 1 0 0

1 item 4.1 2.9 No evidence, or

2 items 5.9 4.2 insufficient evidence, of 

3 items 7.5 5.4 hunger among children

4 items 8.8 6.3

5 items 9.6 6.9

6 items 10.4 7.5 Clear evidence of hunger

7 items 11.5 8.2 among children

8 items1 12.2 8.7

1Scores for households that affirmed no items or all eight items are not defined under the assumptions of the Rasch model. Here the score for households that

affirmed no items is, by convention, shown as zero, but researchers should make allowance in associative models for the fact that the distance between this

score and that of households that affirmed one item is not meaningful. The score for households that affirmed all eight items is calculated at a raw score of 7.5.

This score can be used for most analyses without distorting the fit of associative models, since these households typically represent a very small proportion of

all households.

Source: Calculated by ERS based on August 1998 Current Population Survey Food Security Supplement data to be consistent with the national benchmark

scores presented in Bickel et al., 2000.

17 The discrimination of an item refers to the rapidity with

which the probability of affirmation of the item increases or

decreases as household scores diverge from the item score. For the

average item in a scale that is fit on the logistic metric, the probability of affirmation by a household with severity one unit above

the severity of the item is 0.73. For an item in the same scale that

has unusually high discrimination, the probability might be 0.9.
Item fit statistics for the child items scaled with all 18

items and scaled alone are presented in table 8. Data

from the 1995 Food Security Supplement were used to

calculate these statistics because there were no internal

screeners in that year that might affect fit statistics.

Infit can be thought of as a measure of how sharply the

item discriminates compared with other items in the

model. Except for the two items about skipping meals

(a special case discussed below), infits of the child-referenced items when scaled as part of the 18-item scale

ranged from 0.92 to 1.14. As a conventional criterion,

infits between 0.8 and 1.2 are considered quite good,

and 0.7 to 1.3 are acceptable. Thus, the observed infits

of the child items indicate that their discrimination

characteristics were all near the average of the entire

18-item set. The item that asks directly about whether

the children were hungry discriminated somewhat

more sharply than the average item. That is, affirmations by households with severity scores lower than

that of the item and denials by households with scores

higher than that of the item were somewhat rarer than

for the average item in the 18-item scale.18

Infit statistics for the child items scaled alone (i.e.,

without the household and adult items) were somewhat

less consistent. The statistics are not quite comparable

between the two scales because many households with

children that are included in calculating the 18-item

scale are excluded from calculation of the children’s

food security scale because they are “extreme” on the

latter scale. That is, they did not affirm any item in the

child scale, so their responses provide no information

about relative item severities and are excluded from

the Rasch model fitting. Further, the children’s food

security scale, because it is based on fewer items,

provides a less precise measure of severity (rather

like rounding off a length measurement to the nearest

inch). This lower precision also tends to inflate fit

statistics. Four items in the children’s food security

scale, the first two, the fourth, and the fifth had infits

near unity. The item about children not eating enough

discriminated somewhat more sharply than the average, and the most severe item, children not eating for

whole days, did not discriminate as sharply as the

other items.

The lower infit statistics (on both scales) for the two

items on children skipping meals result in part from a

violation of Rasch model assumptions. The Rasch

model assumes that items are independent. These two

items clearly are not. If a household denies that children

skipped meals, they are not asked how often this

occurred, and that item is imputed as a denial. There are

three sets of such dependencies in the 18-item scale.

Analysis (not shown) demonstrates these dependencies

have only a negligible effect on item calibrations, but

they depress the item fit statistics for the dependent

items, and slightly inflate the item fit statistics for the

other items in the scale (by artificially increasing the

average discrimination). To calculate unbiased fit

statistics for the two items about children skipping

meals, we reestimated the children’s food security scale

and fit statistics with each of the two dependent items

excluded in turn. The resulting infit statistics were 0.91

for Child skipped meal and 0.85 Child skipped meals in

3 or more months, much nearer unity than the values

shown in table 8 (0.78 and 0.69 respectively). These

analyses also reduced the infit statistic of the most

severe item, Child did not eat for whole day, to about

1.25. Thus, when the biases associated with the item

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  19

Table 8—Fit statistics of items in children’s food security scale, 1995

Scaled with all 18 Child items

Items, all households scaled alone

Item Infit Outfit Infit Outfit

Relied on a few kinds of low-cost food for children 1.14 1.25 1.08 14.65

Couldn’t feed the children a balanced meal 1.04 .88 .85 2.71

Children were not eating enough 1.07 .87 .74 .81

Cut size of child’s meals 1.00 1.07 1.00 2.71

Child hungry but couldn’t afford more food .92 .82 .95 3.29

Child skipped meal .88 .64 .78 4.56

Child skipped meals, 3 or more months .81 .25 .69 .56

Child did not eat for whole day 1.14 7.95 1.42 30.70

Source: Calculated by ERS based on April 1995 Current Population Survey Food Security Supplement data.

18 It might be thought tempting to use just this single item to

categorize households as to children’s hunger. However, the discrimination of the scale at a selected threshold is substantially

higher than the discrimination of any single item taken alone. 
dependencies are removed, infit statistics for the children’s food security scale were quite good for six items

and acceptable for all eight. 

Outfit statistics for the child-referenced items in the 18-

item scale were, with one exception, smaller than 1.3,

indicating that highly improbable responses were rare.

The exception was the most severe item. The higher

outfit for that item indicates that a few households

affirmed that a child went a whole day without eating,

but affirmed very few other items. When the child

items were scaled alone, outfits were much less consistent, and those for the least severe and most severe

items were quite high. However, outfit can be very

sensitive to a very few highly improbable responses.

Further analysis (not shown) found that the high outfit

of the least severe item, Relied on a few kinds of lowcost food for children, was almost entirely a result of

responses of five households out of the 2,583 nonextreme households used for calculating the scale.

These households affirmed 4, 5, or 6 items, but denied

this particular item. Similarly, the high outfit for the

most severe item, Child did not eat for whole day, was

entirely the result of responses of just two households.

One affirmed this item but denied all other child items.

The second affirmed only this item and the least severe

item. These highly improbable responses may result

from miscoding by an interviewer, inattention or misunderstanding on the part of the respondent, or from

genuine differences in how food deprivation is experienced in different households. Further investigation of

characteristics of these households may cast more light

on their responses. The rarity of these responses, however, suggests that even the highest outfit statistics seen

in the children’s food security scale do not seriously

undermine the reliability of the overall scale.

Another statistic that can be compared across the two

scales is the mean household measurement error. This

is the expected mean measurement error of the severity

score assigned to households with a given raw score if

the data conformed probabilistically to the model

expectations. To make the statistics for the two scales

comparable, we calculated them across a common

group of households—those that were non-extreme on

the children’s food security scale in 1995. The model

error is expressed in the measurement metric, so we

adjusted the metric of the children’s food security scale

so that the item calibrations had the same standard

deviation as the child-specific items on the householdlevel scale, thus making the error estimates comparable.

The larger number of items in the household-level scale

provides a more reliable measure of households’ food

security status, but this is partially offset by the higher

discrimination of the child-specific items when they are

scaled alone. The mean household standard error was

0.80 for the 18-item scale and 1.02 for the children’s

hunger scale. The size of the household measurement

error varies across the range of each scale, however,

and on both scales the threshold relevant for the identification of children’s hunger falls in the range of

minimum measurement error. Thus, the discrimination

of both scales is highest at the severity level most critical for estimating the prevalence of children’s hunger,

and in this range, the measurement errors were nearly

the same, 0.70 for the household-level scale and 0.73

for the child-specific scale. 

Summary

A continuous, interval-level, scale measuring the

extent of food insecurity among children, and also a

categorical measure that identifies households with

hunger among children, can be calculated from the

eight items in the Food Security Core Survey Module

that ask specifically about experiences and conditions

of children in the household. The interval-level children’s food security scale is appropriate for use as a

research tool in associative analyses, while the categorical measure is appropriate for prevalence

estimation and for comparing the prevalence of children’s hunger among subpopulations.

The children’s food security scale is reasonably reliable

and is quite stable across years. The eight items in the

children’s food security scale are strongly ordered in

terms of severity. Both descriptive and Rasch-modelbased statistical analyses indicate that these items form

a coherent scale for measuring the extent of food insecurity—i.e., deprivation in basic food need—among

children in households. The severity-order and relative

severity of the items were stable over 5 years in spite

of a major restructuring of the questionnaire.

The threshold for identifying households with children’s

hunger is consistent—both conceptually and in terms of

the specific response patterns of households near the

threshold—with earlier work on identifying households

with hunger among children. The measure is methodologically conservative: households classified as having

hunger among children have affirmed at least five

items, including at least three items indicating reduced

food intake by the children.

20  Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25 Economic Research Service/USDA
From its inception, the Federal interagency food security measurement project has had a strong interest in

reliably identifying households with hunger among

children by means of the survey and measurement

method it developed. Such identification is needed in

order for research to provide information on the extent

of hunger among children in the U.S. and on the causes

and consequences of this condition. The Food Security

Supplement questionnaire developed by the project

includes a number of items intended to measure the

extent of food deprivation among children as well as

items that ask about coping mechanisms and strategies

used by households to avoid or ameliorate food

deprivation among children.

The team charged with developing measures of household food security based on data from the first CPS

Food Security Survey in 1995 developed a single, unidimensional household food security scale and

identified three thresholds on the scale (Hamilton et

al., 1997a; Hamilton et al., 1997b; Price, Hamilton,

and Cook, 1997). The least severe threshold identifies

households that are food-insecure. The second identifies households in which one or more members

(mostly adults) were hungry at times during the year

because of insufficient resources to buy food. The third

threshold identifies households in which children (if

any in the household) were hungry at times during the

year, and in which adults experienced more severe and

frequent food deprivation, such as going whole days

without eating. Thus, although the “severe hunger”

threshold was specified to identify households with

hunger among children, a combination of child-referenced items and adult-referenced items was used to

classify households vis-à-vis the threshold. This was

consistent with earlier research findings that, in the

United States, children were generally shielded from

hunger at less severe levels of household deprivation

and began to experience hunger only when hunger

among adults in the household reached this more

severe level. 

A single scale calculated from both child- and adultreferenced items is appropriate for identifying

households with hunger among children, provided that

the two sets of items measure primarily the same

dimension of the complex phenomenon of food insecurity. The preliminary work to develop the household

food security scale included exploration of the issue of

dimensionality among the items that were considered

candidates for the scale using both linear and nonlinear

factor analysis (Hamilton et al., 1997b). The nonlinear

factor analysis indicated that the set of 18 food insecurity and hunger items that are included in the food

security scale lie fairly well on a single dimension.

Nevertheless, the children’s food security scale, calculated from only the child-referenced items, identifies a

larger proportion, and somewhat different set, of

households as having hunger among children than

does the household food security scale, even though

equivalent thresholds were used for the two scales.

This suggests that the assumption of unidimensionality

of the 18-item set, while a reasonable and useful

approximation, may not be strictly accurate.

In this chapter, we document the extent of misclassification of households with hunger among children

produced by the household food security scale and the

bias in prevalence rates of children’s hunger that

results. We then revisit the dimensionality question and

find that there is a nontrivial bidimensionality in the

item set, and that the second dimension measures the

extent to which children share in the food deprivation

that exists at the household level. We then examine

characteristics of households that are misclassified as

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  21

Chapter 3

Why the Children’s Food Security 

Scale Is More Reliable than the 

Household Scale for Identifying 

Hunger Among Children 
regards hunger among children by the household food

security scale and find that there are intuitively sensible

reasons for the misclassification, the most important of

which is the age of children.

Bias and Misclassification by the

Household Food Security Scale

The prevalence of hunger among children as measured

by the children’s food security scale was higher than

that measured by the severe hunger category of the

household food security scale in every year from 1995

to 1999 (table 9). There were 14 to 24 percent fewer

households (with children) in the severe hunger category of the household food security scale than were

identified as having hunger among children by the

children’s food security scale. On average across the 5

years, the estimated prevalence rates differed by 20

percent, or about 0.2 percentage points.

The household scale not only fails to identify children’s

hunger in some households that do have hunger among

children (based on the children’s food security scale),

it also classifies some households in the severe hunger

category even though the children’s scale indicates an

absence of hunger among children in those households. Thus, the two scales identify somewhat different

sets of households as having hunger among children.

Table 10 shows the extent of these differences in 1999.

If we take the children’s food security scale as the

standard, the household scale (severe range)

misclassifies as not having hunger among children

(false negatives) 88,000 households of the 219,000

households with hunger among children and

misclassifies as having hunger among children (false

positives) 51,000 households that did not have hunger

among children. Taking as denominator the 219,000

households with hunger among children based on the

children’s food security scale, these misclassifications

amounted to 40.2 percent false negatives, and 23.3 percent false positives. Analysis (not shown) of 1995 and

1998 data found proportions of false negatives and

false positives almost identical to those in 1999. 

Some difference in classification results from the

lower level of precision of the children’s food security

scale. Because it has only eight items, it is somewhat

less precise than the household scale. Analysis not presented here shows that this lower level of precision

accounts for about half of the false negatives, most of

the false positives, and somewhat less than one-fourth

of the bias.

Re-examining the 

Dimensionality Question

The substantial difference in prevalence rates of severe

household hunger and children’s hunger imply that the

child and adult items in the scale do not, in fact, lie on

a single dimension. Hamilton et al. assessed the dimensionality issue in terms of whether all of the items

related strongly enough to the same dimension to justify

including them in a scale to measure that dimension.

They concluded that, “... the RMSR [root mean square

residual] was well within the acceptable range with a

single factor, and was not materially improved by

adding further factors, making the single-factor model

the most parsimonious solution” (Hamilton et al.,

1997b, p. 10). We do not dispute this finding. The 18

items do, in fact, measure primarily a single phenomenon—household food security—and it is appropriate to

include the child-referenced items in the measure of

that phenomenon. What we want to investigate further,

however, is whether any multidimensionality that does

22  Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25 Economic Research Service/USDA

Table 9—Estimated prevalence of households with hunger among children, 1995-99, based on the children’s food security scale and on the household food security scale

Based on severe

hunger category of 

Based on children’s household food 

Year food security scale security scale Difference

Percentage 

1,000 Percent 1,000 Percent points Percent1

1995 416 1.09 325 0.85 -0.24 -21.88

1996 384 1.01 329 .86 -.15 -14.32

1997 310 .81 239 .63 -.18 -22.90

1998 331 .87 252 .66 -.21 -23.87

1999 219 .58 182 .48 -.10 -16.89

1Difference, as a percentage of estimated prevalence based on children’s food security scale.

Source: Calculated by ERS based on Current Population Survey Food Security Supplement data.
exist in the 18 items compromises the reliability of the

scale for identifying households with hunger among

children. The dimesionality issue is somewhat different

in this case. Even a modest extent of bidimensionality

could be problematic. If even a small proportion of

“moderate hunger” households have hunger among

children, the proportional error in the estimated prevalence of children’s hunger could be substantial because

there are many more households classified with moderate hunger than with severe hunger.

To investigate the extent and character of a second

dimension in the 18 items, we carried out a principle

components analysis of the standardized residuals of

the items after extracting the first factor by fitting the

items to a Rasch model. In this procedure, the items

and households are first scaled by Rasch maximum

likelihood methods. Then, for each household, the

residual—the deviation of each item from its expected

value given the household total score—is calculated.19

Each item’s residual is then standardized by dividing

by the model standard error for the item-household

combination.20 Then principal components are

extracted from a correlation matrix of the standardized

residuals.

The principal components analysis reveals a second

factor that is correlated negatively with all child-specific

items and positively with all adult-specific items (table

11).21 The highest positive correlations are with the

most severe adult items, while correlations are close to

zero for two of the three (least severe) general household items. This second factor can be interpreted, then,

as the extent to which households protect children

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  23

19 The observed value of the item is 1 if affirmed, 0 if denied.

The expected value is the probability of the household affirming

the item given the difference between household and item score,

calculated as p=e (h-i) / (1+e (h-i) ), where h is the scale score

(severity of food insecurity) of the household, i is the calibration

score (severity level) of the item, and e is the base of the natural

logarithms.

20 The model standard error of the item-household combination

depends only on the probability of the household affirming the

item (see previous footnote). The model standard error is the

square root of the model variance, which is calculated as v = p(1-

p)2 + (1-p)p2 = (p-p2). Conceptually, this model variance is the

sum of two terms: (1) the squared deviation if the item is affirmed,

weighted by the probability of it being affirmed, plus (2) the

squared deviation if the item is denied, weighted by the probability

of it being denied.

21 This is actually the first factor extracted from the principal

components analysis of the item deviations, but the scale itself

should be considered the first factor in the raw data, although it is

extracted using a nonlinear model.

Table 10—Misclassification of households with hunger among children by the severe hunger category of the household

food security scale, 1999

Children’s hunger status based on children’s food security scale

Food security status based on No hunger

household food security scale among children Hunger among children Total

————----------------------------------------------------------———1,000————----------------------------———----------

Food secure 32,290 0 32,390

Food insecure, without hunger 4,340 0 4,340

Food insecure with moderate hunger 984 88 1,072

(False negative: 0.23%

of households, 40.2%

of households with

hunger among children)

Food insecure with severe hunger 51 131 182

(0.48%)1

(False positive: 0.13%

of households; 23.3%

of households with hunger

among children)

Total 37,665 2,191 37,884

(0.58%)1

1Prevalence rates of households with children’s hunger as measured by the two scales, i.e., percentage of all households with children.

Source: Calculated by ERS based on April 1999 Current Population Survey Food Security Supplement data.
from hunger by accepting more severe levels of adult

hunger. The factor is of only modest strength, accounting for about 15 percent of the shared variance of the

residuals. This is consistent with the assessment by

Hamilton et al. (1997b) that the phenomenon represented by these items is largely unidimensional. Still,

the factor is strong enough to account for the fact that

some households with hunger among children do not

register severe household-level hunger.22

Which Households Are Misclassified 

by the Household Scale?

Differences between the prevalence of children’s

hunger based on the children’s food security scale and

the prevalence of severe hunger based on the household scale varied among demographic and economic

categories of households, and the differences shed

some light on why the two measures differ (table 12).

Data from the 2 years, 1998 and 1999, were combined

for these calculations to reduce sampling variation.

The most notable variation is across categories based

on the age of the oldest child in the household. The

severe range of the household scale overestimates by

48 percent the prevalence of children’s hunger in

households with no child older than 5 years, and

underestimates by 33 percent and 20 percent the prevalence of children’s hunger in the two older age groups.

This indicates that younger children are protected from

hunger at much more severe levels of food deprivation

among adults than are older children. The bivariate

association of the prevalence bias with age is nonmonotonic—it is highest for the middle of the three age

categories. However, as will be seen below in the

regression analysis, this is an artifact of associations

with other household characteristics. The relationship

becomes monontonic when other characteristics are

controlled. Table 12 also points to substantial bivariate

associations of bias of the household scale with family

structure, number of children, race and ethnicity,

household income, and metropolitan/nonmetropolitan

residence. 

The characteristics that mediate the relationship

between severity as measured by the household scale

and severity as measured by the children’s scale are

interrelated, and their effects are therefore better

assessed in a multivariate context. This was accomplished by estimating a logistic regression of hunger

among children, as measured by the children’s food

security scale, on severe hunger, as measured by the

household scale, and a set of dummy variables for the

household characteristics (table 13). A dummy was

also added for year of survey, since the observed

prevalence of children’s hunger was substantially

lower in 1999 than in 1998.

With controls for the household classification vis-à-vis

the severe hunger threshold and other relevant characteristics, the effects of almost all the characteristics

make intuitive sense. The age of the oldest child in the

24  Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25 Economic Research Service/USDA

22 In principle, this bidimensionality also affects the accuracy

with which the household scale represents hunger among adults.

However, this effect is negligible at the household-level (i.e., adult)

hunger threshold except in households with only very young children. Analysis (not shown) found that for all households with

children, the prevalence rate of hunger among adults based on the

18-item household scale differed by only 0.1 percentage point

from that based on the 10-item scale that excludes the child items

(i.e., the standard scale used for households without children).

However, among households in which the oldest child was 2 years

old or younger, the 18-item scale understated the prevalence of

adult hunger by about 20 percent compared with the 10-item scale.

Table 11—Factor loadings of the first factor extracted

by principal components from the correlation matrix of

the standardized deviations of items from their expected

values given the household score

Item Loading

Household items:

Worried food would run out 0.04

Food bought didn’t last .03

Couldn’t afford to eat balanced meals -.24

Adult-specific items:

Adults cut size of meals or skipped meals .42

Respondent ate less than felt he/she should .30

Adult cut size of meals or skipped meals,

3 or more months .40

Respondent hungry but didn’t eat .38

Respondent lost weight .33

Adults did not eat for whole day .62

Adults did not eat whole day, 3 or more months .60

Child-specific items:

Relied on a few kinds of low-cost food for children -.26

Couldn’t feed the children a balanced meal -.57

Children were not eating enough -.56

Cut size of child’s meal -.35

Child hungry but couldn’t afford more food -.31

Child skipped meal -.43

Child skipped meals, 3 or more months -.38

Child did not eat for whole day -.03

Notes: The analysis is based on households with children who answered at

least one food security or hunger question affirmatively (N=4,340). The

factor explained 15 percent of the total shared variance, or about 2.7 times

the proportion expected under random conditions.

Source: Prepared by ERS based on data from the Current Population

Survey Food Security Supplement, April 1995.
household has a very strong effect. All other things

equal (including the severity level of household

hunger), the odds of observing hunger among children

in which the oldest child is age 6-14 are 5 times the

odds of observing hunger among children in households in which the oldest child is age 0-5. That odds

ratio increases to 7 for households in which the oldest

child is age 15-17. Younger children, especially those

age 5 and under, are protected from hunger at more

severe levels of adult hunger in the household than are

older children. It should be noted, nevertheless, that

even in households with older children, hunger among

the children was registered in only about one-fourth of

the households with adult hunger (i.e., moderate or

severe household-level hunger).23

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  25

Table 12—Difference between prevalence rates of children’s hunger estimated from the household food security scale

and the children’s food security scale, average 1998-99, by household characteristics

Difference: household scale

Households with Households less children’s scale

hunger among children with severe hunger As proportion As proportion

based on children’s based on household of all households of households with 

Household characteristics food security scale food security scale with children children’s hunger

Percent

All households 0.72 0.57 -0.15 -20.8

Family structure:

Two-parent family .34 .24 -.10 -29.4

Single mother with children 1.80 1.49 -.31 -17.2

Single father with children .85 .59 -.26 -30.6

Number of children:

One .63 .58 -.05 -7.9

Two .58 .46 -.12 -20.7

Three or more 1.17 .75 -.42 -35.9

Age of oldest child:

0-5 .25 .37 .12 48.0

6-14 .69 .46 -.23 -33.3

15-17 1.2 .96 -.24 -20.0

Sex of children:

Boys only .72 .62 -.10 -13.9

Girls only .58 .48 -.10 -17.2

Both .85 .61 -.24 -28.2

Race/ethnicity of reference person:

White non-Hispanic .47 .43 -.04 -8.5

Black 1.37 1.07 -.30 -21.9

Hispanic 1.27 .87 -.40 -31.5

Income of household:

Below 130% of poverty line 2.33 1.83 -.50 21.5

Above 130% of poverty line .31 .27 -.04 -12.9

Residence:

Metro .72 .55 -.17 -23.6

Nonmetro .73 .65 -.08 -11.0

Notes: Tabled values are population estimates based on household weights prepared by the Census Bureau for the Food Security Supplement. The unweighted

number of cases is 27,377.

Source: Prepared by ERS based on data from the U.S. Census Bureau Current Population Survey Food Security Supplements, August 1998 and April 1999.

23 The statistics for this comparison are not shown in the table.

In 1998 and 1999, among households in which the oldest child

was age 15-17, 4.7 percent registered adult hunger (i.e., moderate

or severe household hunger), while only 1.2 percent registered

hunger among children on the children’s food security scale.
Household income also has a strong effect on the

extent to which children are protected from hunger.

All other things equal (including the severity level of

household hunger), the odds of observing hunger

among children in households with income below

130 percent of the poverty line are 3 times the odds

of observing hunger among children in households

with income above that level. Households with higher

incomes are likely to experience shorter spells of

food stress and are thus better able to avoid hunger

among children. Higher income households also may

have more resources to draw on to avoid hunger

among children. Adults may “tighten their belts” and

skip a few meals to avoid selling assets, refinancing a

home, or taking an undesirable job, but they may

resort to these exigencies to avoid subjecting their

children to hunger.

Household structure also affects the extent to which

children are protected from hunger, although the

effects are not as strong as those of household income

and the age of children. All other things equal (including the severity level of household hunger), the odds of

observing hunger among children in households headed

by a single parent are 1.8 times the odds of observing

hunger among children in two-parent households. In

part, this effect results from income effects not captured by the single dummy variable. In a logistic

26  Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25 Economic Research Service/USDA

Table 13—Logistic regression of children’s hunger on severe household hunger and household characteristics

Household characteristics Coefficient Odds ratio Significance

Intercept -8.66

Household severe hunger 6.58 718.00 <0.001

Two-parent family (reference)

Single mother with children 0.63 1.88 .008

Single father with children .61 1.84 .121

Other household with children1 .50 1.65 .421

One child in household (reference)

Two children in household .10 1.11 .718

Three or more children in household .37 1.45 .267

Oldest child age 0-5 (reference)

Oldest child age 6-14 1.60 4.97 <.001

Oldest child age 15-17 1.96 7.08 <.001

Boys only .13 1.14 .666

Girls only .20 1.22 .519

Both boys and girls (reference)

White non-Hispanic (reference)

Black .66 1.94 .017

Hispanic .95 2.59 .001

Other non-Hispanic 1.37 3.92 <.001

Below 130% of poverty line 1.10 3.00 <.001

Above 130% of poverty line (reference)

Metro (reference)

Nonmetro -.07 .93 .775

1998 sample (reference)

1999 sample -.21 .81 .316

1Children in this category are not related to the reference person. These include children of an unmarried housemate or partner, foster children, and other

unrelated children.

Logistic regression analysis was based on unweighted household data. Households with no children or with missing income information were excluded.

Number of cases was 25,620.

Source: Prepared by ERS based on data from the U.S. Census Bureau Current Population Survey Food Security Supplements, August 1998 and April 1999.
regression analysis (not shown) with income-to-poverty

ratio entered as a third-order polynomial instead of the

single dummy variable, the effects of single-parent

household structure declined by about one-third. Even

after controlling more adequately for income, however,

it still appears that single parents may be less able than

two parents to protect their children from hunger, even

by accepting more severe levels of hunger themselves.

Race and Hispanic ethnicity have surprisingly strong

effects on the relationship between hunger among children and severe household hunger. All other things

equal (including the severity level of household

hunger), the odds of observing hunger among children

in minority households are 1.9 to 3.9 times those in

non-Hispanic White households. Analysis (not shown)

revealed that about one-third of this effect also resulted

from income effects not captured by the single dummy

variable. The remainder may result from cultural differences associated with race and ethnicity that affect

either the way food deprivation is managed or the way

it is discussed and described (Nord and Jemison, 1999).

Neither sex of children nor metropolitan/nonmetropolitan residence had substantial effects on children’s

hunger once the severity level of household hunger and

other characteristics were controlled. The small effects

observed were not nearly statistically significant.

Summary

Accurate measurement of the extent to which children

are affected by resource-constrained food shortage is

important for understanding the causes and consequences of children’s hunger. Children do not usually

experience resource-constrained hunger until hunger

among adults in the household has reached quite

severe levels. But the extent to which children are protected from, or share in, the food deprivation in a

resource-constrained household is not the same in all

households. There is convincing evidence that a nontrivial second dimension exists in the 18 items in the

food security scale, a dimension measuring the extent

to which children are protected from hunger at the cost

of more severe hunger among adults. As a result, the

18-item food security scale misclassifies a substantial

proportion of households with regard to the level of

severity of food deprivation among children and understates the prevalence of hunger among children by

about 20 percent at the national level. The children’s

food security scale, based on the eight questions in the

food security scale that ask specifically about conditions among children in the household, identifies

households with hunger among children more reliably

than does the household food security scale. 

The extent to which children are protected from

hunger at the cost of more severe adult deprivation is

associated with household characteristics in ways that

are, for the most part, intuitively sensible. In particular,

younger children, especially those age 5 and under, are

protected from hunger up to more severe levels of

adult hunger than are older children. Children in

households with higher income are protected from

hunger up to more severe levels of adult hunger than

are children in lower income households. Children in

two-parent households are protected from hunger up to

more severe levels of adult hunger than are children in

single-parent households. These associations provide a

reasonable explanation of the difference between

prevalence rates based on the two scales. They also

underscore the superiority of the children’s food security scale for comparing prevalence rates of children’s

hunger across demographic and economic groups,

since the extent of bias associated with the household

scale varies across many of the groups of interest.

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  27
References

Anderson, S.A. (ed.). 1990. “Core Indicators of

Nutritional State for Difficult-to-Sample Populations,”

Journal of Nutrition 120(11S):1557-1600.

Andrews, Margaret, Mark Nord, Gary Bickel, and

Steven Carlson. 2000. Household Food Security in

the United States, 1999. Food Assistance and

Nutrition Research Report No. 8. Washington, DC:

Economic Research Service, U.S. Department of

Agriculture.

Bickel, Gary, Steven Carlson, and Mark Nord. 1999.

Household Food Security in the United States,

1995-1998, Advance Report. Alexandria, VA: Office

of Analysis, Nutrition, and Evaluation, Food and

Nutrition Service, U.S. Department of Agriculture.

Bickel, Gary, Mark Nord, Cristofer Price, William L.

Hamilton, and John T. Cook. 2000. Guide to

Measuring Household Food Security, Revised 2000.

Alexandria, VA: Office of Analysis, Nutrition, and

Evaluation, Food and Nutrition Service, U.S.

Department of Agriculture.

Carlson, Steven J., Margaret S. Andrews, and Gary W.

Bickel. 1999. “Measuring Food Insecurity and

Hunger in the United States: Development of a

National Benchmark Measure and Prevalence

Estimates,” Journal of Nutrition 129:1S-7S

(February, Supplemental Issue).

Cook, John T., Maureen Black, Patrick Casey, Deborah

Frank, Carol Berkowitz, and Nieves Zaldivar. 2001.

“Food Insecurity Associated with Health Risks

among Young Children and Their Caregivers:

Results from the Children’s Sentinel Nutrition

Assessment Project (C-SNAP).” Paper presented at

the annual meetings of the Federation of American

Societies for Experimental Biology, Orlando, FL,

March 31-April 4.

Fitchen, Janet M. 1981. Poverty in Rural America: A

Case Study. Boulder, CO: Westview Press.

Fitchen, Janet M. 1988. “Hunger, Malnutrition, and

Poverty in the Contemporary United States: Some

Observations on Their Social and Cultural Context,”

Food and Foodways, 2:309-333.

Hamilton, William L., John T. Cook, William W.

Thompson, Lawrence F. Buron, Edward A.

Frongillo, Jr., Christine M. Olson, and Cheryl A.

Wehler. 1997a. Household Food Security in the

United States in 1995: Summary Report of the Food

Security Measurement Project. Alexandria, VA:

Office of Analysis, Nutrition, and Evaluation, Food

and Nutrition Service, U.S. Department of

Agriculture.

Hamilton, William L., John T. Cook, William W.

Thompson, Lawrence F. Buron, Edward A.

Frongillo, Jr., Christine M. Olson, and Cheryl A.

Wehler. 1997b. Household Food Security in the

United States in 1995: Technical Report.

Alexandria, VA: Office of Analysis, Nutrition, and

Evaluation, Food and Nutrition Service, U.S.

Department of Agriculture.

Nord, Mark, Margaret Andrews, and F. Joshua

Winicki. 2000. “Frequency and Duration of Food

Insecurity and Hunger in U.S. Households.” Paper

presented at the Fourth International Conference on

Dietary Assessment Methods, Tucson, AZ,

September 17-20.

Nord, Mark and Gary Bickel. 1999. “Estimating the

Prevalence of Children’s Hunger from the Current

Population Survey Food Security Supplement.”

Paper presented at the Second Food Security

Measurement and Research Conference, Alexandria,

VA, February 1999. 

Nord, Mark and Kyle Jemison. 1999. “Effects of

Cultural Differences on the Measurement of Food

Insecurity and Hunger.” Paper presented at the

annual meeting of the Rural Sociological Society,

Chicago, IL, August 4-8.

Price, Cristofer, William L. Hamilton, and John T.

Cook. 1997. Household Food Security in the United

States: Guide to Implementing the Core Food

Security Module. Alexandria, VA: Office of

Analysis, Nutrition, and Evaluation, Food and

Nutrition Service, U.S. Department of Agriculture.

Radimer, K.L., C.M. Olson, J.C. Greene, C.C.

Campbell, and J.P. Habicht. 1992. “Understanding

Hunger and Developing Indicators to Assess it in

Women and Children,” Journal of Nutrition

Education 24(1):36S-44S.

Radimer, K.L., C.M. Olson, and C.C. Campbell. 1990.

“Development of Indicators to Assess Hunger,”

Journal of Nutrition 120(Suppl 11):1544-1548.

Wehler, C.A., R.I. Scott, and J.J. Anderson. 1992. “The

Community Childhood Hunger Identification

Project: A Model of Domestic Hunger—

Demonstration Project in Seattle, Washington,”

Journal of Nutrition Education 24(1):29S-35S.

28  Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25 Economic Research Service/USDA
Questionnaire transition into module—administer

to all households: These next questions are about the

food eaten in your household in the last 12 months,

since (current month) of last year, and whether you

were able to afford the food you need.

General food sufficiency question/screener:

Questions 1, 1a, 1b (OPTIONAL: These questions

are NOT used in calculating the food security

scale.) Question 1 may be used as a screener: (a) in

conjunction with income as a preliminary screen to

reduce respondent burden for higher income households only; and/or (b) in conjunction with the 1st stage

internal screen to make that screen more “open”—i.e.,

provide another route through it. 

1. [IF ONE PERSON IN HOUSEHOLD, USE “I”

IN PARENTHESES, OTHERWISE, USE

“WE.”]

Which of these statements best describes the

food eaten in your household in the last 12

months: –enough of the kinds of food (I/we)

want to eat; –enough, but not always the kinds of

food (I/we) want; –sometimes not enough to eat;

or, –often not enough to eat?

[1] Enough of the kinds of food we want to eat

[SKIP 1a and 1b]

[2] Enough but not always the kinds of food we

want [SKIP 1a; ask 1b]

[3] Sometimes not enough to eat [Ask 1a; 

SKIP 1b] 

[4] Often not enough [Ask 1a; SKIP 1b] 

[ ] DK or Refused (SKIP 1a and 1b)

1a. [IF OPTION 3 OR 4 SELECTED, ASK] Here are

some reasons why people don’t always have

enough to eat. For each one, please tell me if that

is a reason why YOU don’t always have enough to

eat. [READ LIST. MARK ALL THAT APPLY.]

YES NO DK

[ ] [ ] [ ] Not enough money for food

[ ] [ ] [ ] Not enough time for shopping or

cooking

[ ] [ ] [ ] Too hard to get to the store

[ ] [ ] [ ] On a diet

[ ] [ ] [ ] No working stove available

[ ] [ ] [ ] Not able to cook or eat because of

health problems

1b. [IF OPTION 2 SELECTED, ASK] Here are

some reasons why people don’t always have the

quality or variety of food they want. For each

one, please tell me if that is a reason why YOU

don’t always have the kinds of food you want to

eat. [READ LIST. MARK ALL THAT APPLY.]

YES NO DK

[ ] [ ] [ ] Not enough money for food

[ ] [ ] [ ] Kinds of food (I/we) want not

available

[ ] [ ] [ ] Not enough time for shopping or

cooking

[ ] [ ] [ ] Too hard to get to the store

[ ] [ ] [ ] On a special diet

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  29

Appendix A

U.S. Household Food Security Survey 

Module: 3-Stage Design 

(2 Internal Screeners)
BEGIN FOOD SECURITY/HUNGER CORE

MODULE (i.e., SCALE ITEMS)

NOTE: The children’s food security scale is based on

the child-referenced items: 5-7 and 13-16.

Stage 1: Questions 2-6—ask all households:

[IF SINGLE ADULT IN HOUSEHOLD, USE “I,”

“MY,” AND “YOU” IN PARENTHESES; OTHERWISE, USE “WE,” “OUR,” AND “YOUR

HOUSEHOLD;” IF UNKNOWN OR AMBIGUOUS,

USE PLURAL FORMS.]

2. Now I’m going to read you several statements

that people have made about their food situation.

For these statements, please tell me whether the

statement was often true, sometimes true, or

never true for (you/your household) in the last

12 months, that is, since last (name of current

month).

The first statement is “(I/We) worried whether

(my/our) food would run out before (I/we) got

money to buy more.” Was that often true, sometimes true, or never true for (you/your

household) in the last 12 months?

[ ] Often true

[ ] Sometimes true

[ ] Never true

[ ] DK or Refused

3. “The food that (I/we) bought just didn’t last, and

(I/we) didn’t have money to get more.” Was that

often, sometimes, or never true for (you/your

household) in the last 12 months?

[ ] Often true

[ ] Sometimes true

[ ] Never true

[ ] DK or Refused

4. “(I/we) couldn’t afford to eat balanced meals.”

Was that often, sometimes, or never true for

(you/your household) in the last 12 months?

[ ] Often true

[ ] Sometimes true

[ ] Never true

[ ] DK or Refused

[IF CHILDREN UNDER 18 IN HOUSEHOLD, ASK

Q5-6; OTHERWISE SKIP TO 1st Level Screen.]

5. “(I/we) relied on only a few kinds of low-cost food

to feed (my/our) child/the children) because (I

was/we were) running out of money to buy

food.” Was that often, sometimes, or never true

for (you/your household) in the last 12 months?

[ ] Often true

[ ] Sometimes true

[ ] Never true

[ ] DK or Refused

6. “(I/We) couldn’t feed (my/our) child/the children) a

balanced meal, because (I/we) couldn’t afford

that.” Was that often, sometimes, or never true

for (you/your household) in the last 12 months?

[ ] Often true

[ ] Sometimes true

[ ] Never true

[ ] DK or Refused

1st level Screen (screener for Stage 2): If AFFIRMATIVE RESPONSE to ANY ONE of Questions

2-6 (i.e., “often true” or “sometimes true”) OR

response [3] or [4] to Question 1 (if administered),

then continue to Stage 2; otherwise, skip to end.

Stage 2: Questions 7-11—ask households passing

the 1st level Screen: (estimated 40% of households

< 185% Poverty; 5.5% of households > 185%

Poverty; 19% of all households).

[IF CHILDREN UNDER 18 IN HOUSEHOLD, ASK

Q7; OTHERWISE SKIP TO Q8]

30  Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25 Economic Research Service/USDA
7. “(My/Our child was/The children were) not eating

enough because (I/we) just couldn’t afford

enough food.” Was that often, sometimes, or

never true for (you/your household) in the last

12 months?

[ ] Often true

[ ] Sometimes true

[ ] Never true

[ ] DK or Refused

8. In the last 12 months, since last (name of current

month), did (you/you or other adults in your

household) ever cut the size of your meals or

skip meals because there wasn’t enough money

for food?

[ ] Yes

[ ] No (SKIP 8a)

[ ] DK or R (SKIP 8a)

8a. [IF YES ABOVE, ASK] How often did this happen—almost every month, some months but not

every month, or in only 1 or 2 months?

[ ] Almost every month

[ ] Some months but not every month

[ ] Only 1 or 2 months

[ ] DK or R

9. In the last 12 months, did you ever eat less than

you felt you should because there wasn’t enough

money to buy food?

[ ] Yes

[ ] No 

[ ] DK or R

10. In the last 12 months, were you ever hungry but

didn’t eat because you couldn’t afford enough

food?

[ ] Yes

[ ] No 

[ ] DK or R

11. In the last 12 months, did you lose weight

because you didn’t have enough money for

food?

[ ] Yes

[ ] No 

[ ] DK or R

2nd level Screen (screener for Stage 3): If AFFIRMATIVE RESPONSE to ANY ONE of Questions 7

through 11, then continue to Stage 3; otherwise,

skip to end.

Stage 3: Questions 12-16—ask households passing

the 2nd level Screen: (estimated 7-8% of households < 185% Poverty; 1-1.5% of households >

185% Poverty; 3-4% of all households).

12. In the last 12 months, did (you/you or other

adults in your household) ever not eat for a

whole day because there wasn’t enough money

for food?

[ ] Yes

[ ] No (SKIP 12a)

[ ] DK or R (SKIP 12a)

12a. [IF YES ABOVE, ASK] How often did this happen—almost every month, some months but not

every month, or in only 1 or 2 months?

[ ] Almost every month

[ ] Some months but not every month

[ ] Only 1 or 2 months

[ ] DK or R

[IF CHILDREN UNDER 18 IN HOUSEHOLD, ASK

13-16; OTHERWISE SKIP TO END.] 

13. The next questions are about children living in

the household who are under 18 years old. In the

last 12 months, since (current month) of last

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  31
year, did you ever cut the size of (your

child’s/any of the children’s) meals because there

wasn’t enough money for food?

[ ] Yes

[ ] No 

[ ] DK or R

14. In the last 12 months, did (your child/any of the

children) ever skip meals because there wasn’t

enough money for food?

[ ] Yes

[ ] No (SKIP 14a)

[ ] DK or R (SKIP 14a)

14a. [IF YES ABOVE ASK] How often did this happen—almost every month, some months but not

every month, or in only 1 or 2 months?

[ ] Almost every month

[ ] Some months but not every month

[ ] Only 1 or 2 months

[ ] DK or R

15. In the last 12 months, (was your child/were the

children) ever hungry but you just couldn’t

afford more food?

[ ] Yes

[ ] No 

[ ] DK or R

16. In the last 12 months, did (your child/any of the

children) ever not eat for a whole day because

there wasn’t enough money for food?

[ ] Yes

[ ] No 

[ ] DK or R

END OF FOOD SECURITY/HUNGER CORE

MODULE

32  Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25 Economic Research Service/USDA
This appendix describes procedures that researchers

can use to calculate the children’s food security scale

from CPS Food Security Survey data. This includes

the operational steps required to:

z Code the survey responses collected using the core

CPS Food Security Survey module into the format

needed to calculate the children’s food security scale

z Calculate the children’s food security scale, which is

an interval-level measure of the severity of food

deprivation among children in the household

z Classify households as to whether children have

been hungry due to lack of household resources for

food.

It is assumed that the child-referenced items are collected in the context of the entire 18-item module.24

(The food security core module questionnaire is

included in appendix A.) Detailed instructions for calculating the household-level food security measures

are available in Guide to Measuring Household Food

Security, Revised 2000 (Bickel et al., 2000). We summarize here some of the material from the Guide that

is needed to calculate the children’s food security scale

and provide additional detail that is specific to this

scale. Readers should consult the Guide for additional

information.

Coding Survey Responses for the Food

Security Scale

NOTE: If the child-referenced items have already been

recoded in order to calculate the household food security scale, there is no need for further recoding, and

this subsection may be skipped.

In order to determine a household’s score on the children’s food security scale, it is first necessary to code

their response to each of the child-referenced items as

either “affirmative” or “negative.” Some of this coding

is obvious because the only response choices are “yes”

or “no.” Two groups of questions, however, have less

obvious response categories, and responses missing

because of screening may need to be dealt with. The

procedure for coding these questions is described

below and summarized in table B-1.

Questions Q5, Q6, and Q7 have three response categories: “often true,” “sometimes true,” and “never

true.” For these questions, “often true” and “sometimes

true” are considered affirmative responses because

they indicate that the condition occurred at some time

during the year. The distinction between the “often”

and “sometimes” responses is not used in the scale.

Question Q14a is a followup question whose response

categories are “almost every month,” “some months

but not every month,” and “only 1 or 2 months.” For

purposes of the scale, the first two responses are considered affirmative and the third is considered

negative.25 Thus, the negative condition on these indicators is “only 1 or 2 months” while the positive, or

affirmative, is that the condition occurred in 3 months

or more during the year. Q14a is coded negative for

households that are skipped over this question because

they responded “no” to Q14. Q14a is coded missing

for households that are skipped over it because they

responded “don’t know” or refused to answer Q14.

Questions that a household does not answer because it

has been screened out are coded as negative responses.

The household was screened out precisely because it

was deemed, on the basis of earlier information, not to

have experienced the conditions represented in those

questions.

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  33

Appendix B

Implementing the Children’s 

Food Security Scale

24 It is probably practical to collect just the child-referenced

items, but to date there is no research evidence as to whether

response to these items is affected substantially if they are asked

outside of the context of the full module.

25 Thus, households that report that children skipped meals in

only 1 or 2 months register a single affirmative response (for Q14),

while those reporting that children skipped meals in 3 or more

months register two affirmative responses, one for Q14 and one for

Q14a.
Any other question that a household fails to answer,

for any reason other than being screened out or

skipped over, is coded as “missing” (i.e., item nonresponse). This includes all responses with codes such as

“don’t know” or “refused to answer.”

Assigning Children’s Food Security

Scale Scores to Households and

Classifying Households as to Children’s

Hunger Status

Both the children’s food security scale (the continuous,

interval-level measure of food deprivation among children) and the categorical measure identifying

households with hunger among children can be computed from the eight child-referenced items. The two

measures and their applications are described in detail

in chapter 2. This section specifies how to calculate

each measure from the child-referenced items, recoded

as described above.

For households with valid responses to all the childreferenced items, that is, with no responses coded as

“missing” after the recoding described above, both

scale score and categorical assignment can be read

directly from table 7. More severe food deprivation,

represented by a higher number of affirmative responses, is represented by a higher scale score. Two metrics

are in common use, and both are presented in table 7.

One is a linear transformation of the other, so the

choice is a matter of preference.26 The score of zero

for households with no affirmative responses is arbitrary. The appropriate score for these households

cannot be determined by the measurement model,

34  Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25 Economic Research Service/USDA

Table B-1—Coding survey responses for items in the children’s food security scale

Question Negative responses Affirmative responses Missing data

Number Question (Code = 0) (Code = 1) (Code = .)

Q5 Relied on a few kinds Never true Often true; Refused; 

of low-cost food for (or screened out at Sometimes true Don’t know

children preliminary screen)

Q6 Couldn’t feed the Never true Often true; Refused;

children a balanced (or screened out at Sometimes true Don’t know

meal preliminary screen)

Q7 Children were not Never true Often true; Refused;

Eating enough (or screened out at Sometimes true Don’t know

preliminary or 1st- level

Q13 Cut size of child’s No (or screened out at Yes Refused;

Meals preliminary, 1st, or 2nd Don’t know

level screen)

Q14 Children ever No (or screened out at Yes Refused;

skipped meal preliminary, 1st, or 2nd Don’t know

level screen)

Q14a Children skip meals, Only 1 or 2 months; Almost every month; Refused;

3 or more months Skipped because of “no” Some months but not Don’t know

on Q14; (or screened out every month

at preliminary, 1st, or 2nd

level screen)

Q15 Children hungry but No (or screened out at Refused;

Couldn’t afford more preliminary, 1st, or 2nd Yes Don’t know

Food level screen)

Q16 Children did not eat No (or screened out at Yes Refused;

for whole day preliminary, 1st, or 2nd Don’t know

level screen)

Note: Include options in italics in coding criteria when screens are used; if screens are not used, disregard.

26 Researchers working on scaling issues will generally prefer

the “computational metric,” because it is a logit-unit metric. See

Guide to Measuring Household Food Security, Revised 2000

(Bickel et al., 2000), Appendix C, for further information on alternative units of measure used in U.S. food security reports and data

products and the relationships among them.
except that it is known to be lower than the score of

households that affirmed one item, and may vary from

household to household. Researchers should take this

into consideration when carrying out analyses that

include households with raw scores of zero.

If any households have missing responses to the items

in the children’s food security scale after recoding as

described above, the choice must be made either to utilize one of several direct imputation methods to

replace missing values with imputed affirmative or

negative responses, or to employ Rasch model software to calculate household scale values. The direct

imputation method described below is simple, and in

most cases is quite adequate for the small proportion

of missing values typically found in CPS Food

Security Survey data. Using Rasch methods has the

advantage of applying a sophisticated statistical imputation formula for the missing data, but requires

special software as well as considerable statistical

background and programming experience. Rasch

methods may be needed if large proportions of

responses are missing, or if the same item is missing

for a large proportion of households, as may result

from survey administration problems. For detailed

information on imputation and an overview of Raschmodel capabilities, see Guide to Measuring Household

Food Security, Revised 2000 (Bickel et al., 2000).

If missing values for the child-referenced items have

already been imputed in the context of the entire 18

items, those imputed responses may be retained for the

children’s food security scale. Alternately, the following procedure can be used to impute missing responses

based just on the child-referenced items.

1. Preparatory to imputation, order the eight items

by severity:

1st (Q5) Relied on a few kinds of low-cost

food for children

2nd Q6) Couldn’t feed the children a balanced

meal

3rd (Q7) Children were not eating enough

4th (Q13) Cut size of children’s meals

5th (Q15) Children were hungry but couldn’t

afford more food

6th (Q14) Children skipped meals

7th (Q14a) Children skipped meals in 3 or

more months

8th (Q16) Children did not eat for whole day

2. Impute “yes” to a missing item if, for that household, there is a valid affirmative response to at

least one item more severe than the missing item

and no negative response to any item less severe

than the missing item.

3. Impute all other missing items as “no.” (Note

that this procedure is methodologically conservative, tending to minimize false positives.)

4. Determine if cases with very few valid responses

have enough information to be imputable, or if

the entire case should be declared missing (i.e.,

unscalable—children’s hunger status unknown).

There are no hard and fast rules for this. It

depends somewhat on how good you believe the

partial data that you have are. If a household

gave no valid responses to any of the child-referenced items, then it should almost certainly be

declared unscalable. Note that a household could

refuse all of the first stage questions and then be

skipped out of the rest of the questionnaire at the

1st level screener. For such a household, it is

probably not appropriate to score the skipped

questions as “no” responses. Rather, those

responses also should be assigned as missing and

the household classified as unscalable—children’s hunger status unknown.

Following imputation of any missing responses, children’s food security scale score and categorical

assignment for these households can be read directly

from table 7 based on the number of items affirmed by

the household. Any items imputed as affirmative are

included in the count of affirmative responses.

Economic Research Service/USDA Measuring Children’s Food Security in U.S. Households, 1995-99/FANRR-25  35