Relative validity and reliability of a food frequency questionnaire for a triethnic population of 1-year-old to 3-year-old children from low-income families

Objective: To develop and validate a food frequency questionnaire (FFQ) for low-income, 1- to 3-year-old Hispanic, African-American, and white children. Design: A convenience sample of low-income mothers provided dietary data for their child via FFQs and 3-day diet records. Subjects/setting: Participants (N=77) were recruited from Special Supplemental Program for Women, Infants, and Children clinics and public health clinics. All subjects were Hispanic, African-American, or white mothers of children 1 to 3 years old, 18 years of age or older, income less than 200% of the federal poverty level, and were literate in English. Statistical analyses performed: Wilcoxon signed-ranks tests were used for comparisons of food group servings on time 1 and time 2 FFQs and to examine differences in food group servings between the FFQ and diet records. Spearman correlations were calculated to assess test-retest reliability and the relative validity. Contingency tables were used to determine the degree of association between the FFQ and diet records. Results: Reliability correlations were significant for all nine food categories (̄x=0.69), ranging from 0.53 (soups) to 0.84 (nonstarchy vegetables). Validity correlations were significant for all food groups (̄x=0.41) except starchy vegetables. Thirty-six percent of children were classified into the same quartile of food group intake and 78% into the same or within one quartile. Conclusions: The FFQ yielded excellent reliability and acceptable validity and can be used to assess food choices in a triethnic sample of low-income 1- to 3-year-old children.