Conventional energy and macronutrient variables distort the accuracy of children's dietary reports: Illustrative data from a validation study of effect of order prompts

• Published in: Preventive medicine 2007-01, Vol.44 (1), p.34-41
• Main Authors: Baxter, Suzanne Domel, Smith, Albert F, Hardin, James W, Nichols, Michele D
• Format: Article
• Language: English
• Subjects: Bias; Carbohydrate; Child; Diet Records; Dietary Carbohydrates - administration & dosage; Dietary Fats - administration & dosage; Dietary Proteins - administration & dosage; Energy; Energy Intake; Fat; Feeding Behavior - psychology; Female; Food Services; Humans; Internal Medicine; Macronutrients; Male; Mental Recall; Nutrition Surveys; Observation; Order prompts; Protein; Reproducibility of Results; Schools; Sex Factors; Validation studies of dietary reports
• ISSN: 0091-7435; 1096-0260
• DOI: 10.1016/j.ypmed.2006.07.011

Abstract Objective. Validation-study data are used to illustrate that conventional energy and macronutrient (protein, carbohydrate, fat) variables, which disregard accuracy of reported items and amounts, misrepresent reporting accuracy. Reporting-error-sensitive variables are proposed which classify reported items as matches or intrusions, and reported amounts as corresponding or overreported. Methods. 58 girls and 63 boys were each observed eating school meals on 2 days separated by ≥ 4 weeks, and interviewed the morning after each observation day. One interview per child had forward-order (morning-to-evening) prompts; one had reverse-order prompts. Original food-item-level analyses found a sex-x-order prompt interaction for omission rates. Current analyses compared reference (observed) and reported information transformed to energy and macronutrients. Results. Using conventional variables, reported amounts were less than reference amounts ( p s < 0.001; paired t -tests); report rates were higher for the first than second interview for energy, protein, and carbohydrate ( p s ≤ 0.049; mixed models). Using reporting-error-sensitive variables, correspondence rates were higher for girls with forward- but boys with reverse-order prompts ( p s ≤ 0.041; mixed models); inflation ratios were lower with reverse- than forward-order prompts for energy, carbohydrate, and fat ( p s ≤ 0.045; mixed models). Conclusions. Conventional variables overestimated reporting accuracy and masked order prompt and sex effects. Reporting-error-sensitive variables are recommended when assessing accuracy for energy and macronutrients in validation studies.