Characteristics of energy under-reporting in children and adolescents

Under-reporting (UR) of food intake is an issue of concern, as it may distort the relationships studied between diet and health. This topic has been scarcely addressed in children. The objective of the study was to assess the extent of UR in French children and investigate associated covariates. A total of 1455 children aged 3–17 years were taken from the nationally representative cross-sectional French étude Individuelle Nationale des Consommations Alimentaires (INCA2) dietary survey (2006–7). Food intake was reported in a 7 d diet record. Socio-economic status, sedentary behaviour, weight perception variables and food habits were collected by questionnaires. Weight and height were measured. Under-reporters were identified according to the Goldberg criterion adapted to children. Multivariate logistic regressions investigated the associations between UR and covariates. Rates of under-reporters were 4·9 and 26·0 % in children aged 3–10 and 11–17 years, respectively (P < 0·0001), without significant differences between boys and girls. Overall, UR was positively associated with a lower socio-economic status, overweight, skipping breakfast and dinner, a higher contribution of proteins to energy intake (EI), and a lower contribution of simple carbohydrates to EI. Under-reporters aged 3–10 years also had a higher sedentary behaviour and a lower snack-eating frequency. In adolescents, UR was also associated with a less-frequent school canteen attendance, a perception of being overweight, a wish to weigh less, and current and past restrictive diets. In conclusion, under-reporters differ from plausible reporters in several characteristics related to diet, lifestyle, weight status and socio-economic status. Therefore, it is important to consider this differential UR bias when investigating diet–disease associations in children.

A systematic review of the validity and reliability of sedentary behaviour measures used with children and adolescents

The aim of this review was to evaluate the reliability and validity of methods used to assess the multiple components of sedentary behaviour (i.e. screen time, sitting, not moving and existing at low energy expenditure) in children and adolescents. Twenty-six studies met our inclusion criteria and were reviewed. Thirteen studies reported the reliability of self- and proxy-report measures of sedentary behaviour and seven of these were found to have acceptable test–retest reliability. Evidence for the criterion validity of self- and proxy-report measures was examined in three studies with mixed results. Seven studies examined the reliability and/or validity of direct observation and the findings were generally positive. Five studies demonstrated the utility of accelerometers to accurately classify sedentary behaviour. Self-report measures provide reliable estimates of screen time, yet their validity remains largely untested. While accelerometers can accurately classify participants’ behaviour as sedentary, they do not provide information about type of sedentary behaviour or context. Studies utilizing measures of sedentary behaviour need to more adequately report on the validity and reliability of the measures used.We recommend the use of objective measures of sedentary behaviour such as accelerometers, in conjunction with subjective measures (e.g. self-report), to assess type and context of behaviour.

Family holiday decision making : the knowledge and influence of adolescent children and parents

This paper investigates the influence adolescent children have over their parents with regards to holiday decisions. A dyadic method of analysis was used to determine the level of influence young people have on the decision making oftheir parents. Our research shows that the families in general do not see their adolescent children as more knowledgeable than the parents when it comes to holidays. However, the level of knowledge the family perceives the child to have is strongly related to how much influence the child then has over the parent. Also, the level of 'expertness' the family attribute to the child is strongly related to the family's attitude towards the child as a socialisation agent for the parent. Parents knowledge on the other hand, is not related to how influenced they are by their children. Finally, daughters have a larger impact on their parents' holiday decisions than sons.

Integrating time-series hydroacoustics and video observations for detecting changes in benthic habitats

The ability to quantify change in marine benthic habitats must be considered a key goal of marine habitat mapping activities. Changes in distribution of distinct suites of benthic biological species may occur as a result of natural or human induced processes and these processes may operate at a range of temporal and spatial scales. It is important to understand natural small scale inter-annual patterns of change in order to separate these signals from potential patterns of longer term change. Work to describe these processes of change from an acoustic remote sensing stand point has thus far been limited due to the relatively recent availability of full coverage swath acoustic datasets and cost pressures associated with multiple surveys of the same area. This paper describes the use of landscape transition analysis as a means to differentiate seemingly random patterns of habitat change from systematic signals of habitat transition at a shallow (10–50 m depth) 18 km2 study area on the temperate Australian continental shelf between the years 2006 and 2007. Supervised classifications for each year were accomplished using independently collected high resolution (3 m cell-size) multibeam echosounder (MBES) and video-derived reference data. Of the 4 representative biotic classes considered, signals of directional systematic changes were observed to occur between a shallow kelp dominated class, a deep sessile invertebrate dominated class and a mixed class of kelp and sessile invertebrates. These signals of change are interpreted as inter-annual variation in the density and depth related extent of canopy forming kelp species at the site, a phenomenon reported in smaller scale temporal studies of the same species. The methods applied in this study provide a detailed analysis of the various components of the traditional change detection cross tabulation matrix allowing identification of the strongest signals of systematic habitat transitions across broad geographical regions. Identifying clear patterns of habitat change is an important first step in linking these patterns to the processes that drive them.

Assessing dietary intake in children and adolescents : considerations and recommendations for obesity research

Dietary intake and food habits are important contributors to the obesity epidemic. They are highly modifi able components of energy balance and are usually targeted in both obesity prevention and treatment programs. However, measurement of total diet creates challenges and can convey a large burden in terms of cost, technical expertise, impact on respondents and time. It is not surprising therefore that comprehensive reports of dietary intake in children are uncommon and, when reported, have limitations. The aim of this paper is to guide researchers and practitioners in selecting the most appropriate dietary assessment method for situations involving children and adolescents. This paper presents a summary of the issues to consider when choosing a method, a description of some of the more commonly used dietary assessment methods for young people and a series of case-studies to illustrate the range of circumstances faced when measuring dietary intake. We recommend that researchers consider the specifi c components of dietary intake addressed in their research and practice, and whether diet should be reported comprehensively or as targeted components. Other considerations include age, cognitive ability, weight status, physical activity level, respondent burden, and reliability and validity in the context of program goals and research questions. A checklist for selecting the appropriate dietary methodology is provided. This guide aims to facilitate the reporting of dietary intake and food habits in the context of obesity using valid and reliable measures, thus contributing to the evidence-base for nutrition policies and programs relating to obesity.

Scores on the dietary guideline index for children and adolescents are associated with nutrient intake and socio-economic position but not adiposity 1-3

Diet quality indices reflect overall dietary patterns better than single nutrients or food groups. The study aims were to develop a measure of adherence with dietary guidelines applicable to child and adolescent populations in Australia and determine the association between index scores and food and nutrient intake, socio-demographic characteristics, and measures of adiposity. Data were analyzed from 4- to 16-y-old participants of the 2007 Australian Children’s Nutrition and Physical Activity Survey (n = 3416). The Dietary Guideline Index for Children and Adolescents (DGI-CA) comprises 11 components: 5 core food groups, wholegrain bread, reduced-fat dairy foods, extra foods (nutrient poor and high in fat, salt, and added sugar), healthy fats/oils, water, and diet variety (possible score of 100). The index criteria were age specific. The mean DGI-CA score was low (53.6 ± 0.4), similar between boys and girls, and differed by age; the youngest children scored higher than the oldest children (P < 0.0001). Higher DGI-CA scores were associated with lower energy intake, energy density, total and saturated fat, and sugar intake; higher protein, carbohydrate, fiber, calcium, iron, vitamin C, vitamin A, folate, phosphorous, magnesium, zinc, and iodine intakes; and a higher polyunsaturated:saturated fat ratio (P < 0.0001). DGI-CA scores were associated with socio-economic characteristics and measures of family circumstance. Weak positive associations were observed between DGI-CA score and BMI or waist circumference Z-scores in the 4- to 10-y and 12- to 16-y age groups only. This index is the first validated index in Australia and one of the few international indices to describe the diet quality of children and adolescents.