Children's estimates of food portion size: the development and evaluation of three portion size assessment tools for use with children

Abstract

A number of methods have been developed to assist subjects in providing an estimate of portion size but their application in improving portion size estimation by children has not been investigated systematically. The aim was to develop portion size assessment tools for use with children and to assess the accuracy of children's estimates of portion size using the tools. The tools were food photographs, food models and an interactive portion size assessment system (IPSAS). Children (n 201), aged 4-16 years, were supplied with known quantities of food to eat, in school. Food leftovers were weighed. Children estimated the amount of each food using each tool, 24 h after consuming the food. The age-specific portion sizes represented were based on portion sizes consumed by children in a national survey. Significant differences were found between the accuracy of estimates using the three tools. Children of all ages performed well using the IPSAS and food photographs. The accuracy and precision of estimates made using the food models were poor. For all tools, estimates of the amount of food served were more accurate than estimates of the amount consumed. Issues relating to reporting of foods left over which impact on estimates of the amounts of foods actually consumed require further study. The IPSAS has shown potential for assessment of dietary intake with children. Before practical application in assessment of dietary intake of children the tool would need to be expanded to cover a wider range of foods and to be validated in a 'real-life' situation.Portion size estimation: Food photographs: Interactive portion size assessment system: ChildrenTo monitor the diet of populations there is a need for methods that are accurate, easy for the subject to complete and appropriate to the target population.Assessing habitual food intake of any population group is challenging. Common problems encountered include underreporting 1,2 , subject selection bias and recording bias 3 . Additional limitations must be considered when children are the subjects. The skills and limitations of the population to be studied must be considered. When children are the subjects these may include issues of literacy and writing skills, limited food recognition skills, memory constraints and concentration span.In order that intakes of food can be converted into intakes of nutrients or other food constituents, a measure or estimate of the portion size of each food item consumed is required. Weighing and recording all foods eaten requires a highly motivated and committed subject population that is unlikely to be representative of the general population. Berg et al. discuss that when participation in a project requires a great deal of subject commitment or divulging information of a sensitive nature then there is a risk that the response rate will be low 4 . Of those approached to take part, 64 % completed the recent National Diet and Nutrition Survey (NDNS) of young people aged 4-18 years in the UK, which used a 7 d weighed diary method 5 . In addition, ap...

Feasibility of 2 × 24-h dietary recalls combined with a food-recording booklet, using EPIC-Soft, among schoolchildren

“…The smallest portions of the various picture series were chosen for the youngest children much more frequently than the larger portions, indicating that the pictures series may not show the most appropriate portion sizes for children in this age group. It has been shown that children's estimates using age-appropriate photographs were more accurate than when using photographs designed for adults (Foster et al, 2006(Foster et al, , 2008(Foster et al, , 2009. In the present study, units and HHMs were used more often for quantification than the picture book, and the participants found it more difficult to use HHM than the picture book.…”

Estimation of portion size in children's dietary assessment: lessons learnt

“…Three portion size assessment tools were developed using three different media. These were food photographs, food models and a novel Interactive Portion Size Assessment System (IPSAS) (Foster et al, 2008).…”

“…For further details on methodology refer Foster (2003), Anderson et al (2005) and Foster et al (2008).…”

“…When children are responsible for reporting their own intake issues of literacy, writing skills, memory constraints and concentration span are of particular concern. From previous studies (Foster, 2003;Anderson et al, 2005;Foster et al, 2008), a personal observation is that there is a great deal of variation in the ability to recall foods consumed within any one age group. This may be dependent on an individual's cognitive development, interest in food, and the attention paid to mealtimes.…”

“…Three portion size assessment tools were developed using three different media. These were food photographs, food models and a novel Interactive Portion Size Assessment System (IPSAS) (Foster et al, 2008).The foods selected for inclusion in the feasibility study were foods commonly consumed by children in four age groups from 4-16 years. The principal data source was the National Diet and Nutrition Survey: young people aged 4-18 years (Gregory and Lowe, 2000).…”