Albert F. Smith

The National Health and Nutrition Examination Survey’s food insecurity questionnaire was administered to 155 children (77 African American, 65 white, 13 “other” [7 Hispanic; 6 mixed races]) in grade 4 twice, 28–32 days apart. Test-retest reliabilities were modest and somewhat similar for assessment mode (classroom, interview) and subgroup variables (gender, race, socioeconomic status, academic achievement, body mass index percentile, social desirability). As academic achievement increased, white and other children reported less food insecurity, and African American children reported slightly less. As social desirability increased, white and African American children reported slightly more food insecurity, and other children reported substantially more. Although the questionnaire may be acceptable for use with diverse groups of children in grade 4, validation is needed.

To investigate the relationship of reporting accuracy in 24-h dietary recalls to child-respondent characteristics—cognitive ability, social desirability, body mass index (BMI) percentile and socioeconomic status (SES). Fourth-grade children (mean age 10.1 years) were observed eating two school meals and interviewed about dietary intake for 24 h that included those meals. (Eight multiple-pass interview protocols operationalized the conditions of an experiment that crossed two retention intervals—short and long—with four prompts (ways of eliciting reports in the first pass)). Academic achievement-test scores indexed cognitive ability; social desirability was assessed by questionnaire; height and weight were measured to calculate BMI; nutrition-assistance program eligibility information was obtained to index SES. Reported intake was compared to observed intake to calculate measures of reporting accuracy for school meals at the food-item (omission rate; intrusion rate) and energy (correspondence rate; inflation ratio) levels. Complete data were available for 425 of 480 validation-study participants. Controlling for manipulated variables and other measured respondent characteristics, for one or more of the outcome variables, reporting accuracy increased with cognitive ability (omission rate, intrusion rate, correspondence rate, PPP=0.001) and was better by higher- than by lower-SES children (intrusion rate, P=0.001). Some of these effects were moderated by interactions with retention interval and sex. Children’s dietary-reporting accuracy is systematically related to such respondent characteristics as cognitive ability, social desirability, BMI percentile and SES.

Validation-study data were analysed to investigate retention interval (RI) and prompt effects on the accuracy of fourth-grade children’s reports of school-breakfast and school-lunch (in 24-h recalls), and the accuracy of school-breakfast reports by breakfast location (classroom; cafeteria). Randomly selected fourth-grade children at ten schools in four districts were observed eating school-provided breakfast and lunch, and were interviewed under one of eight conditions created by crossing two RIs (‘short’ – prior-24-hour recall obtained in the afternoon and ‘long’ – previous-day recall obtained in the morning) with four prompts (‘forward’ – distant to recent, ‘meal name’ – breakfast, etc., ‘open’ – no instructions, and ‘reverse’ – recent to distant). Each condition had sixty children (half were girls). Of 480 children, 355 and 409 reported meals satisfying criteria for reports of school-breakfast and school-lunch, respectively. For breakfast and lunch separately, a conventional measure – report rate – and reporting-error-sensitive measures – correspondence rate and inflation ratio – were calculated for energy per meal-reporting child. Correspondence rate and inflation ratio – but not report rate – showed better accuracy for school-breakfast and school-lunch reports with the short RI than with the long RI; this pattern was not found for some prompts for each sex. Correspondence rate and inflation ratio showed better school-breakfast report accuracy for the classroom than for cafeteria location for each prompt, but report rate showed the opposite. For each RI, correspondence rate and inflation ratio showed better accuracy for lunch than for breakfast, but report rate showed the opposite. When choosing RI and prompts for recalls, researchers and practitioners should select a short RI to maximise accuracy. Recommendations for prompt selections are less clear. As report rates distort validation-study accuracy conclusions, reporting-error-sensitive measures are recommended.

A validation study of children's dietary reporting provided an opportunity to investigate whether cognitive ability is a source of systematic error in dietary recalls. From the fall of 2004 through the spring of 2007, fourth-grade children (n = 374) in Columbia, South Carolina, were observed eating school meals and interviewed to obtain 24-hour dietary recalls; subsequently, measures of dietary reporting error were calculated. The common factor extracted from 4 subject-area achievement tests (scores on which were provided by the school district for 362 children) was used as a measure of cognitive ability. For the 325 children who reported school meals that met the criteria to be reports about school meals, as cognitive ability increased, dietary reporting error decreased; the relation between cognitive ability and dietary reporting performance was stronger among girls than among boys. The mean cognitive ability for 37 children who reported no meals that satisfied the criteria for being reports about school meals was significantly lower than that for the 325 children who reported meals that satisfied these criteria. These findings indicate that cognitive ability is a source of systematic error in children's dietary recalls. More generally, the quality of epidemiologic survey data may depend systematically on the cognitive ability of respondents.