Martin James Tovée

Childhood obesity is a major health concern and a public health priority. Parents play a key role in addressing childhood obesity, and one possible solution could be directly informing parents about their child’s weight status, encouraging them to change behaviour. The MapMe intervention has been developed as a tool to improve parental acknowledgement and understanding of childhood obesity. A three-arm cluster randomised trial was delivered within England’s mandatory National Child Measurement Programme as part of the MapMe2 study. Building on the original MapMe trial, it assessed the effect of two versions MapMe intervention on weight in children aged 4–5 and 10–11 years. The aim of this study was to conduct a within-trial cost-utility analysis (CUA) using the MapMe2 trial data to estimate the potential cost-effectiveness of two versions of the MapMe intervention (a ‘Web Only’ version and a ‘Web Boost’ version) compared to a control group. The CUA was carried out from an NHS perspective over a one-year time horizon. In the base case, the primary outcome was child health-related quality of life measured by the CHU-9D. The inclusion of out-of-pocket costs and an alternative measure of health-related quality of life (the WAItE) were conducted as sensitivity analyses. Results were expressed as incremental cost per Quality Adjusted Life Year (QALY) gained. The results indicated that the ‘Web Only’ and ‘Web Boost’ intervention versions were more likely to be cost-effective than the control. This conclusion held true even when including parental out-of-pocket expenses for weight management and physical activity, and when using a condition-specific health-related quality of life measure. However, given the small sample size in the sub-study, the results from this study should be treated with a high degree of caution. Future analysis should focus on estimating the cost-effectiveness of public health interventions such as MapMe over a longer time horizon, given that full costs and benefits are unlikely to be captured in the short time frame of trials such as MapMe2.

Body dissatisfaction (BD) often arises from the discrepancy between a person's perceived body and an ‘ideal’ body. Mass media's adult‐targeted body ‘ideals’ also reach children and shape their body perceptions. BD is arising at increasingly younger ages in global north populations, however, there is scant research investigating media impacts on children's body perceptions in Latin American contexts. We longitudinally investigated the relationships of television viewing, age and gender with children's body size perceptual accuracy and child and adult body size ideals among Nicaraguan primary school children ( N = 170) living in rural communities with systematically varying media access. As expected, general body size accuracy increased with age. Girls, and not boys, who watched more television desired slimmer adult bodies, and showed greater own‐body size accuracy. Findings show shared and context‐specific patterns compared with global north samples, with media and developmental maturation each shaping different aspects of body perception.

Young adults are a high-risk group for weight-related health problems but are often overlooked in weight management intervention design. Validated visual tools that accurately depict body size are needed to improve communication and intervention strategies. This study validated innovative, photo-realistic, gender-specific body size scales of young adults (aged 18), created from 3D scans to depict systematic changes in adiposity. A total of 110 young adults (aged 18–25) completed two behavioural tasks: (1) estimating the relative size of the bodies and (2) ranking them in ascending order of weight. To assess reliability, participants repeated the tasks three days later. Participants accurately estimated relative body sizes and ranked the images in line with the systematic BMI changes across the scales. Test–retest analyses showed good to excellent reliability for both tasks. The young adult body size scales are anthropometrically accurate, reliable, and valid tools for body size estimation tasks. They provide a robust resource for research, clinical communication, and intervention design focused on young adults.

Background/objectives: This study addresses two questions: what body sizes/shapes do participants believe correspond to the boundaries of the National Child Measurement Programme (NCMP) weight categories for children aged 4–5 and 10–11 years old, and are these judgements altered by using terminology encouraging positive action by parents? Methods: The study used photorealistic computer-generated stimuli based on 388 3D scans of children in a method of adjustment task. We first asked participants to estimate the boundaries between weight status categories as described by the NCMP. To test validity, we asked a second set of participants to estimate the body that represented exemplars of each weight category (the exemplars should fall between the boundary estimates). We then recruited a third set of participants to determine whether substituting positive action terminology for the weight status definitions altered the boundary positions. Results: First, validity was confirmed. Second, we found a compressed response range (lower weights overestimated and higher weights underestimated) for the positioning of both categorical boundaries and exemplars. Finally, the use of alternative weight status terminology resulted in an upward shift in the position of all boundaries in the BMI spectrum but failed to remove the compressive stimulus response effect. Discussion: There is a disconnect between the child size that people perceive to correspond to the different weight categories and the size criteria used by health professionals, and it is likely that this gap can only be bridged by training to recognise the medically based categories.

Objectives: Parental underdetection of child underweight and overweight/obesity may negatively affect children's longer‐term health. We examined psychological/behavioural mechanisms of a very low‐intensity intervention to improve acknowledgement and understanding of child weight after feedback from a school‐based weight monitoring programme. Design: This sub‐study was nested within a larger 3‐arm cluster‐RCT (1:1:1; N = 57,300). Parents in all groups received written postal feedback on their child's weight classification. Intervention participants received an enhanced feedback letter with computer‐generated photorealistic images depicting children of different weight classifications, and access to a website about supporting healthy weight, once (intervention one) or twice (intervention two; repeated 6 months after first ‘dose’). Methods: A quantitative process and outcome evaluation using baseline and 12‐month BMI z ‐scores of an opt‐in sub‐sample of 502 children aged 4–5 and 10–11. Children completed dietary reports, used accelerometers (MVPA), and self‐reported self‐esteem; 10–11‐year‐olds also self‐reported quality of life and dietary restraint. Parents reported perceptions of child's weight classification, and their intentions, self‐efficacy, action planning and coping planning for child physical activity, dietary intake; parents of 4–5‐year‐olds reported their child's quality of life. Results: Neither intervention differentially improved parental acknowledgement or understanding of weight classification at follow‐up, although parents in all groups reported better acknowledgement after receiving feedback. The interventions did not affect behavioural/psychological determinants, weight outcomes, children's self‐esteem, dietary restraint or quality of life. Conclusions: The interventions neither improved parental acknowledgement of child weight, child BMI z ‐scores and their psychological/behavioural determinants, nor worsened psycho‐social sequelae.

Objectives: Parents infrequently recognize childhood overweight/obesity and healthcare professionals (HCPs) also struggle to visually identify it, potentially limiting the offer and uptake of weight management support. This study examined perceptual and attitudinal/cognitive determinants of child weight judgements amongst parents and HCPs to identify targets for intervention. Design: We used a mixed experimental design with parents and HCPs as the between‐participants factor. Stimulus gender, age and BMI centile were the within‐participant repeated measures factors. Methods: One hundred and fifty‐six HCPs and 249 parents of children aged 4–5 or 10–11 years viewed simulated child images. They estimated their relative size and categorized the weight status of each figure. Stimuli were photo‐realistic figural scales based on 3D‐scans of 4‐ to 5‐ and 10‐ to 11‐year‐old children varying in adiposity. Participants also reported their beliefs about causes, controllability and categorization of child weight. Results: Both groups accurately estimated the figures' relative size. However, categorization of higher weight figures was poor, demonstrating a mismatch between perceptual judgements of size and categorization of weight status. Lower levels of comfort with assigning ‘overweight’ categorizations to children, and a stronger belief that weight was controllable by the child/parent, predicted less accurate weight status categorizations. Conclusions: Parental and HCP misperceptions when categorizing children's higher weight are related to attitudinal/cognitive factors, including reluctance to label a child's weight status as overweight and beliefs about whether a child's weight can be controlled by them or their family.

Background/Objectives: It is vital to identify children whose weight status means that they may benefit from medical or behavioural support, but adult visual judgements of child weight status are inaccurate, and children are seldom routinely weighed and measured. Consequently, there is a need for validated visual tools for use in training, communication, and interventions relating to child weight. Methods: This paper presents validation data for a set of innovative photo-realistic colour body size scales depicting boys and girls aged 4–5 and 10–11. Each age- and gender-specific scale consists of 7 figures based on three-dimensional (3D) scans of 388 children to accurately represent the change in body size caused by changing adiposity. To assess scale validity, 238 adult participants (105 men, 132 women, 1 non-binary individual) undertook two tasks: rating figure adiposity using a visual analogue scale and ranking figures in ascending order of adiposity (OSF Reference: gdp9j). Results: Participants accurately estimated the relative adiposity of each figure, i.e., they were able to tell the difference between figures and correctly rank them by size. This demonstrates scale validity for use in body size tasks. One hundred and fifty-one participants also provided 3-day test–retest data, which demonstrates excellent short-term reliability. Conclusions: Overall, the MapMe child body size scales provide an anthropometrically accurate, valid, reliable, and usable tool for size-related tasks and communication with adults regarding child weight.