Methods to develop a 2-Item food security screen

Background: Food Security is access by all household members at all times to enough food for an active, healthy life. It includes at a minimum: 1) ready availability of nutritionally adequate and safe foods and 2) assured ability to acquire acceptable foods in socially acceptable ways. The 18-item US Household Food Security Scale (HFSS) is used to monitor the household food security status of the nation annually. Although the HFSS is widely used in research, its length may prohibit clinical use. Methods: A sample of 30,098 caregivers of children under 3 years of age from 7 urban medical centers completed the 18-item HFSS as part of the Children's HealthWatch Surveillance Study. The prevalence of endorsement for each of the 18-items was ascertained. The first two questions were the most frequently endorsed. Sensitivity and specificity analysis were performed to determine if a positive response to question 1 and/or 2 would yield acceptable values when compared to the “gold standard” HFSS. Results: The screen yielded a sensitivity of 97% and a specificity of 83%. A logistic regression model was run to determine the c-statistic or how well the screen predicts the gold standard. The c-statistic is equal to the area under the “receiver operating characteristic” curve (ROC). This value was 0.90. Discussion: FI is a serious public health concern for families with young children. The 2-item screen can be readily used in clinical settings as a quick screen for identifying families that may otherwise go undetected.