Exploratory and confirmatory factory analysis of the Willingness to Eat Whole Grains Questionnaire: A measure of young adults' attitudes toward consuming whole grain foods

Whole grains are recommended by dietary guidelines because of their health-promoting properties, yet attitudes toward consuming these foods have not been examined. This study developed and validated a questionnaire to estimate willingness to consume whole grain foods. Focus group interviews with high school students and input from nutrition educators produced a list of 10 whole grain items that were included in the “Willingness to Eat Whole Grains Questionnaire”. Young adult university students 18-29 years of age indicated their willingness to consume each of the whole grain foods using a 4-point, Likert-type scale with responses ranging from “always unwilling” to “always willing” and a fifth option of “never eaten”. Participants' age, race/ethnicity, and gender were collected. Data were examined using exploratory factor analysis (EFA), confirmatory factor analysis (CFA), and test-retest reliability. The EFA test (n = 266; 65% female; 69% white) using principal axis factoring returned a single factor that included all survey items and explained 58.3% of the variance. The CFA (n = 252; 62% female, 74% white) supported a single-factor solution: χ2 = 80.57 (35); RMSEA = 0.07; Comparative Fit Index = 0.92; Tucker-Lewis Index = 0.90; and SRMR = 0.05. The questionnaire, administered on two occasions separated by two weeks to 36 university students, demonstrated good testretest reliability (r = 0.87, p < 0.0001). The “Willingness to Eat Whole Grains Questionnaire” had good face validity when used with a young adult population and will be a useful tool to help nutrition educators examine attitudes toward consuming nutrient-rich whole grain foods.