BACKGROUND
Few diet quality indices have been developed and validated for use among children and adolescents. Additionally, many available indices require completion of burdensome dietary assessments.
OBJECTIVE
We aimed to calculate and evaluate the performance of a modified version of the food-based Prime Diet Quality Score (PDQS) derived from different diet assessment methods conducted at four time points in a single study population from childhood through adolescence.
METHODS
Among 1,460 child participants in the Project Viva cohort, we calculated the PDQS in early and mid-childhood and early and mid-adolescence using dietary data obtained from Food Frequency Questionnaire (early childhood, parent report), PrimeScreen (mid-childhood, parent report and early adolescence, self report) and 24-hour recall (mid-adolescence, self report). We evaluated construct and relative validity and internal reliability of the score in each life stage.
RESULTS
The PDQS showed a range of scores at all life stages and higher scores were associated with intake of many health-promoting macro- and micronutrients (e.g. protein, fiber and vitamins) in early childhood and mid-adolescence. The PDQS performed similarly to the Youth Healthy Eating Index/Healthy Eating Index (Spearman r=0.63-0.85) in various assessments. Higher PDQS was associated with expected characteristics including more frequent breakfast eating, family dinners, and vigorous physical activity; with less frequent TV viewing and fast-food intake; and with more sleep and higher maternal diet scores during pregnancy. Cross-sectional associations of the PDQS with various anthropometric measurements and biomarkers were inconsistent but generally in the expected directions (e.g. higher PDQS associated with lower triglycerides and insulin and higher HDL cholesterol). Internal reliability was consistent with what has been found for other diet quality indices.
CONCLUSIONS
The PDQS can be calculated from data collected using different and brief dietary assessment methods and appears to be a valid and useful measure of overall diet quality in children and adolescents.
CLINICAL TRIAL REGISTRY INFORMATION
Project Viva is registered at clinicaltrials.gov as NCT02820402.