Development and validation of a diet quality index based on recommendations of the Dietary Guidelines for the Argentine Population

Abstract

INTRODUCTION: Diet quality indices are useful tools to assess dietary patterns and adherence to dietary guidelines. The objective was to develop and validate an index based on the Dietary Guidelines for the Argentine Population (GAPA). METHODS: An index based on local dietary guidelines was developed, content validity was analyzed by experts, and construct validity and reliability were analyzed through a cross-sectional study. Healthy adult volunteers were included, and general and food consumption data were collected. The ability to give varied scores and find differences between groups was analyzed. The correlation between the total score and each component, and with energy and nutrient intake was evaluated. Underlying dimensions were explored using principal component analysis. Internal consistency was analyzed using Cronbach’s alpha. RESULTS: An Argentine Diet Quality Index (ICDAr) was developed which reflects eight main messages of the guidelines and was found to be well accepted by experts (Aiken’s V ≥0.8; p<0.05). The ICDAr showed a wide range (37.36-86.39) and a difference between smokers and non-smokers (p=0.002). A positive correlation was found between the total score and each component and a better nutrient intake, but not with energy intake. Multiple underlying dimensions were found. Cronbach’s alpha was 0.49. DISCUSSION: The ICDAr is valid to assess diet quality according to adherence to the GAPA.