Preschool Age Populations Research Needs - NCS Dietary Assessment Literature Review
Drawing conclusions from the validation studies on preschool populations discussed in this chapter is difficult because of the varied study designs, the relatively small study populations, and limited number of studies on each dietary assessment method. Even among studies using the same dietary assessment method, the protocol for the method differed. For example, the 24HR (24-Hour Recall) studies differed in the number of recall passes, the portion size estimating aides, and the number of recall interviews. As in the infant and toddler age group, validation studies in preschool children using larger and more representative populations, similar methodologies, and examining the impact of gender, ethnicity, or infant age on the validity are needed. A comprehensive study evaluating multiple measures of child intake simultaneously would be helpful. In a longitudinal study, the timing and frequency of dietary assessment in preschoolers should be examined.
Research is needed on portion size estimating aides for this age group (126); most of the studies reviewed used adult portion-size estimating aides. Existing validation research has mainly compared estimates of nutrients consumed rather than reported foods. Several investigators have recommended more research on the assessment of the accuracy of reported foods in 24 HR interviews (135;136;139;145). There is a lack of research supporting the best method for collecting information on the preschool child's intake when not with the parent or primary caregiver.
The impact of social desirability on reporting bias has not been examined in preschool populations. Parents may feel reporting their child's intake of foods of questionable nutritional value will reflect negatively on perceived parenting skills. Larger studies examining the effect of gender, BMI (Body-Mass Index) of the parent and child, and ethnicity on errors in reporting are needed. Validation studies in low-literacy populations are needed. The methods research priority recommendations from the "Future Directions for the Integrated CSFII-NHANES" 2002 workshop (9;64) can also be applied to preschool populations. Validation of automated or web-based dietary assessment methods is an additional research need.