| The assessment of reliability and validity of survey questions is essential to collect meaningful data with small measurement errors. The purposes of this study are: (1) to evaluate the reliability and validity of questions on nutrition knowledge, attitudes, and food label use of U.S. adults included in DHKS 1994--1995, and using the results of this analysis; (2) to assess changes in nutrition knowledge, attitudes, and use of the food label (the fist of ingredients, nutrition facts, health claims and nutrient content descriptors) among the U.S. population between DHKS 1994 and 1995. Item total correlation, alpha if item deleted, and Cronbach's alpha were calculated to test reliability. Validity was assessed by content validity, divergent validity, and discriminant validity. Twenty constructs were created from DHKS 1994--1995 in this study: five for nutrition knowledge, 14 for attitude, and one construct for frequency of food label use. Eight of 13 constructs tested had a good reliability with Cronbach's alpha r ≥ 0.70. Fifteen of 20 constructs were valid.;Between 1994 and 1995, nutrition knowledge, attitudes, and food label use were improved. The reliable and valid national survey questions for selected constructs are important to establish theoretical models to understand the relationships among nutrition knowledge, attitudes, use of food label, and dietary intakes in the future. |
