Preschool-aged children in the U.S. have suboptimal diets. Interventions to improve child nutrition focus on parents and their role in shaping social and physical home environments, which influence children’s eating behaviors. Dietary assessment tools selected to measure intervention objectives, and how results are interpreted in key findings, are essential when examining children’s diets. Dietary assessment tools can be used to capture habitual or acute dietary intake as well as a variety of dietary outputs—foods and food groups consumed (e.g., fruits and vegetables), energy (calories), macronutrients (carbohydrates, fats and protein), micronutrients (vitamins and minerals), and dietary scores or quality indices (e.g., diet diversity, Healthy Eating Index).
1. Introduction
Early childhood is a period for growth and development and when eating habits and dietary behaviors are formed. Nutrition is a critical contributor to overall health and plays a vital role in the prevention of diet-related chronic diseases, such as obesity
[1]. Unfortunately, young children in the United States (U.S.) have poor diet quality
[2] and they continue to fall short in achieving adequate intake of nutritious foods, particularly vegetables, whole grains, and dairy
[3]. Conversely, children have high consumption of added sugars, sodium and saturated fat when compared to the recommendations of the Dietary Guidelines for Americans
[3]. U.S. children aged 2- to 5 years consume approximately 75 percent of daily energy intake at home, emphasizing the important role parents and the home food environment have on influencing children’s dietary intake
[4][5]. The home is the child’s first food and eating environment, is fundamental in shaping the emergence of eating habits in early childhood and continues to be a critical environment throughout childhood
[5].
Interventions targeting dietary intake and eating behaviors of preschool-aged children are increasingly focused on parents as agents of change, largely due to the extensive evidence supporting parents’ influence on shaping children’s eating and growth
[6][7][8]. In families with young children, parents are widely considered the gatekeepers of the home environment
[9], and as such, substantially contribute to the physical and social aspects of the home that may impact child dietary intake as well as weight status. The physical home food environment is influenced by food availability (physically in the home), accessibility (within reach by hand of the child), and purchasing behaviors (frequency of acquisition, socioeconomic position, and taste preferences)
[10][11]. Socially, children’s eating behaviors are influenced by parent feeding styles and practices
[12], expectations for diet
[13][14], role modeling
[13], and mealtime routines
[6]. A growing body of evidence demonstrates the influence of the physical and social environments on dietary intake in children
[15]. Accurate dietary assessment measures are needed to describe children’s diet, demonstrate dietary improvements via nutrition interventions, and better understand how the home environment influences dietary intake
[16].
The degree of accuracy that is required to assess young children’s diets depends on the context and whether the selected tool fits the study’s purpose and can answer the stated research question(s)
[17]. With the multidisciplinary nature of obesity research, it can be challenging for researchers to select the best dietary assessment method when designing studies and to appropriately interpret results
[18]. Thus, it is imperative for researchers to understand the nuances between different diet assessment tools, including the dietary outputs produced by the tool and key considerations of use with young children (
Table 1).
Approaches to measure dietary intake in the home environment are primarily self-report methods in which parents/caregivers report on the foods and beverages consumed by their child. These self-report measures include 24 h recall, food records, food frequency questionnaires (FFQ) and screeners, and food checklists. Objective measures, such as food photography and biomarkers (e.g., Veggie Meter), are minimally used in the home setting; however, as technologies continue to emerge, these methods are becoming more feasible
[16][17][18][19].
Dietary assessment tools can be used to capture habitual or acute dietary intake as well as a variety of dietary outputs—foods and food groups consumed (e.g., fruits and vegetables), energy (calories), macronutrients (carbohydrates, fats and protein), micronutrients (vitamins and minerals), and dietary scores or quality indices (e.g., diet diversity, Healthy Eating Index)
[18]. Intervention studies may use these dietary outputs to assess changes in overall diet composition, consumption of specific foods/food groups, intake by eating occasion, or the contribution of nutrients to health outcomes, including obesity. The ability to assess the efficacy and effectiveness of nutrition interventions to produce dietary changes is reliant on the use of psychometrically sound diet assessment tools to capture dietary variables that are in concordance with the intervention design and study objectives.
Key considerations for measuring young children’s diets include the use of a proxy respondent (parent, caregiver), the setting of intake (home, childcare), respondents’ ability to accurately capture child’s diet in a prescribed timeframe (24 h, eating occasion), respondent characteristics (education, literacy and culture) and respondent burden. Given the developmental stage of young children, an adult respondent is the primary source for preschoolers’ diet information. A large proportion of children aged 2–5 years split their days between childcare and home settings
[19], limiting the ability of some adult respondents to accurately report on a child’s diet over a 24 h period, thus raising concerns of recall and reporting bias.
Table 1. Diet assessment tools used with preschool-aged children
[18][20][21][22][23][24].
Dietary Assessment Tool |
Description |
Key Considerations for Use in Preschool-Aged Children |
Respondent |
Diet Intake Captured |
Dietary Variable Outputs |
Single |
Multiple |
Habitual |
Acute |
Foods/ Food Groups |
Energy |
Macro-Nutrients |
Micro- Nutrients |
Score/Index |
24 h Recall |
Facilitated interview by trained professional or automated software to capture amounts of foods and beverages consumed by respondent in past 24 h period. Sample period: 2–3 days, mix of weekday and weekend |
Primary respondent may not be with child for all 24 h. Culturally specific foods can be captured due to open-ended nature of tool. |
✓ |
|
|
✓ |
✓ |
✓ |
✓ |
✓ |
✓ |
Food Record/ Diary |
Written or electronic account of all foods and beverages consumed over a specified timeframe. Items may be weighed or non-weighed. Sample period: 3–7 consecutive days |
Primary respondent may not be with child for all 24 h. Record may be completed across multiple settings (childcare/home, split households). Culturally specific foods can be captured due to open-ended nature of tool. |
✓ |
✓ |
|
✓ |
✓ |
✓ |
✓ |
✓ |
✓ |
FFQ/ FFQ Screener |
Defined list of foods and beverages; asks frequency of consumption over an extended timeframe. Respondents choose from close-ended, multiple-choice options. Usually self-administered but can be interviewer administered/assisted. FFQ contains a comprehensive list of items (~120–180 items). FFQ screeners contain an abbreviated list of the specified items (~20 items) and can be targeted to a specific food group or nutrient. Sample period: 1 W to 6 M (vs. 12 M for adults) |
Complex to navigate and literacy level of respondent should be considered. The FFQ Screener provides only high-level view of intake. List of food items may not include foods commonly consumed in some cultures or child-friendly items. |
✓ |
|
✓ |
|
✓ |
* |
✓ |
✓ |
✓ |
Food Checklist |
Defined list of foods and beverages for which respondents are asked to check which of the specified items were consumed over a specified time period. It may also ask about behavioral habits (e.g., reading nutrition labels). Portion sizes may be captured. Sample period: single or multiple days |
Low participant burden, although literacy level of respondent should be considered. List of food items may not include foods commonly consumed in some cultures or child-friendly items. |
✓ |
|
✓ |
✓ |
✓ |
|
|
|
✓ |
While previous reviews have examined diet assessment tools for children
[25][26][27] few have included preschool-aged children, have restricted inclusion of assessments to short forms (i.e., ≤50 items)
[28] or have narrowly focused on interventions aimed at the physical home food environment without social characteristics. Thus, the objectives of this entry were to: (1) describe the dietary assessment tools used in intervention studies in young children focused within the home environment; and (2) examine how the application of these dietary assessment tools addresses intervention objectives.
2. Dietary Assessment Tools for Preschool-Aged Children in the Home Environment
Findings suggest that dietary assessment tools used with preschool-aged children are most often applied to answer a variety of research questions with no agreement on standards for assessment, including which foods to measure, the time frame to consider, and related social characteristics impacting the home food environment. Further, some but not all intervention objectives matched reported key findings. Collectively, these findings point to challenges in obtaining dietary data on preschool-aged children, particularly with the reliance on parents and caregivers as proxy respondents, as well in interpretation of the data obtained from the self-report dietary measures.
To improve children’s diet, it is necessary to accurately measure their current intake. The accuracy is reliant on validity of the tool itself as well as reliability of the respondents’ input. Reporting the dietary intakes of young children, particularly in the context of obesity, brings with it additional challenges and considerations. These include the need for a proxy respondent (e.g., parent or caregiver), consideration of developmental stage (e.g., cognitive skills), and food consumption away from home
[18]. All studies in this entry used parents or caregivers as respondents, with 7 studies using a 24 h recall or daily food records
[29][30][31][32][33][34][35]. The likelihood of recall and reporting bias are high for proxy respondents, particularly if they are asked to report on 24 h intake in which they are not present for some of the eating occasions or if multiple respondents split the reporting over the 24 h period
[36]. Thus, researchers should consider if a full day’s intake is necessary versus examining eating occasions in which the caregiver is with the child (e.g., dinner) and/or those time intervals in which the intervention is specifically targeting. If the intervention target is on parents serving their children more fruits and vegetables, then collecting dietary data when the child is outside of parental care may not be reliable from a measurement perspective, nor produce a valid intervention effect. Lastly, respondent characteristics such as educational level, reading and digital literacy, and inclusion of food relevant to respondents’ culture (e.g., ethnic background, geographical location) should be considered for accuracy along with respondent burden.
The accuracy of dietary data relies on the use of psychometrically sound tools that are critically assessed with the sample population. The reporting of psychometric properties for the studies included in this entry were limited in detail and scope. Nine studies in this entry did not fully report psychometric properties of reliability and validity
[30][32][33][37][38][39][40][41][42][43] and an additional 3 studies reported sources in which testing was done on populations other than preschool-aged children
[33][37][38]. This illustrates not only the need for better measures for early childhood audiences, but also more awareness and/or training amongst researchers in dietary measurement. This is critical as the use of methods with low validity greatly attenuates the associations between dietary intakes and outcomes in health
[16].
Due to the inherent limitations of self-report diet assessment tools, combined with challenges of working with early childhood audiences and sparse psychometrics, considerations for using multiple methods to maximize the strengths of each instrument may be warranted. The use of alternative approaches to capture diet as well as interpret outputs from dietary measures may provide researchers the ability to answer more clearly defined research questions to strengthen the concordance of intervention objectives and study design. Two studies in this entry coupled self-report dietary data with objectives measures, including food photography and biomarkers (e.g., Veggie Meter)
[37] and a weighed dinner meal
[33] to evaluate different aspects of their intervention. A third study used multiple dietary tools to examine different aspects of their intervention related to an eating occasion, snacking
[35].
As technology becomes more ubiquitous with daily life, utilizing digital devices to capture dietary information in young children has potential. Food photography is an emerging tool for dietary assessment as an image-assisted method to enhance another dietary assessment method, as used in the Bakirci-Taylor et al. (2019) study
[37], or as the primary form of dietary data
[44]. Food photography has been used with preschool audiences to assess a 24 h period
[45] or a single eating occasion, such as lunch
[46] and dinner
[47][48]. In addition to providing energy and nutrients
[48], data produced by food photography has been used to examine dietary quality via the Healthy Meal Index
[47][49] and comparison to dietary recommendations, namely the Child and Adult Care Food Program’s nutritional standards
[46][48]. Lastly, McCloskey et al. (2019)
[47] used food photography to examine the context of foods served to preschoolers in the home environment by examining concordance with mothers’ foods served and timing of meal, as well as food preparation (e.g., takeout to non-convenience). Food photography provides an alternative method to collecting dietary data for preschool audiences as well as innovative approaches to interpreting these data.
In addition to alternative methods, researchers should consider alternative approaches to capturing food or diet-related data beyond just intake. When examining studies in this entry, only 2 studies
[42][50] addressed food availability and accessibility in their interventions, with an additional 2 studies
[33][35] making target foods available to their participants. Both cross-sectional and longitudinal studies demonstrate that home food availability can predict child food intake
[10][51][52]. For instance, a study by Boles et al. (2019)
[10] examined the relationship between the HFE and child dietary intake of preschool-aged children from rural and low-income, culturally diverse families and found that the availability of fruits and vegetables, meat products and sugar sweetened beverages were shown to predict greater intake by preschool children
[10]. Because food availability has been shown to be predictive of dietary intake, researchers may consider using measurement tools that capture the availability of foods in the home as an alternative or complement to dietary intake measures.