assured ability to acquire acceptable foods in socially acceptable ways (e.g., without resorting to emergency food supplies, scavenging, stealing, or other coping strategies).” Food insecurity is defined as “limited or uncertain availability of nutritionally adequate and safe foods or uncertain ability to acquire acceptable foods in socially acceptable ways.” Hunger is defined as the “uneasy or painful sensation caused by a lack of food; the recurrent and involuntary lack of access to food” (Anderson, 1990, pp. 1575–1576).
The USDA estimates of the prevalence of food insecurity are developed using data collected annually in the Food Security Supplement to the Current Population Survey (CPS). The full supplement appears in Appendix A. The food insecurity questions—on whether the household experienced difficulty in meeting basic food needs due to a lack of resources, the severity of food deprivation ranging from “worry about running out of food” to “children ever not eating for a whole day,” and ways of augmenting inadequate food resources—are asked of all households with incomes below 185 percent of the poverty line. Thus households are presumed in USDA’s annual statistical reports to be fully food secure only if their annual incomes are higher than 185 percent of the poverty line and they gave no indication of food access problems on preliminary screener questions and are not asked the questions in the food security assessment series. The questions specify that any behavior or condition must be due to a lack of economic or other resources to obtain food, so the scale is not affected by hunger due to voluntary dieting or fasting or being too busy to eat or other reasons.
On the basis of the number of food insecure conditions that households report (the number of questions the respondent affirms), respondents are classified into one of three categories for purposes of monitoring and statistical analysis of the food security status of the population: food secure, food insecure without hunger, and food insecure with hunger. USDA uses statistical methods based on a single-parameter logistic item-response-theory model (the Rasch model) to assess individual questions and to assess the assumptions that justify using the raw number of items affirmed as an ordinal measure of food insecurity. (This method is described further in subsequent chapters.)