COMPARATIVE ADVANTAGE OF 3-DAY FOOD RECORDS OVER 24-HOUR RECALL AND 5-DAY FOOD FREQUENCY VALIDATED BY OBSERVATION OF 9-YEAR-OLD AND 10-YEAR-OLD GIRLS

Objective The validity of the 24-hour recall, 3-day food record, and 5 -day food frequency was assessed to decide on a dietary assessment met hod for the National Heart, Lung, and Blood Institute (NHLBI) Growth a nd Health Study. Design All subjects were assigned to one of three die tary assessment methods. Unobtrusive observers recorded types and amou nts of foods eaten during lunch, and these were compared with the food s reported by the girls in the study. Setting School lunchrooms in Cal ifornia and Ohio. Subjects 58 girls, aged 9 and 10 years. Main outcome measures Reporting errors for dietary assessment methods. Statistical analyses performed Descriptive statistics, matched Pair t tests, and Spearman correlation coefficients. Results Comparison of the intakes o f energy and selected macronutrients showed different ranges of, and m edian Percentage absolute errors for, each dietary assessment method. Percentage absolute errors ranged between 20 and 33 for the 5-day food frequency method; 19 and 39 for the 24-hour recall; and 12 and 22 for the 3-day food record. The proportion of missing foods (ie, observed food items not reported) and phantom foods (ie, reported food items no t observed) by each method were 46% and 40%, respectively, for the 5-d ay food frequency; 30% and 33%, respectively, for the 24-hour recall; and 25% and 10%, respectively, for the 3-day food record. Applications /conclusions Errors in food reporting and quantification can vary with the type of dietary methodology. Agreement between observed and repor ted intakes from 3-day food records made it the best overall choice. O n this basis, it was selected as the method of assessment for the NBLB I Growth and Health Study.