Arch Dis Child 94:944-949 doi:10.1136/adc.2009.162578
  • Original article

Weight status and perceived body size in children

  1. J Saxton,
  2. C Hill,
  3. P Chadwick,
  4. J Wardle
  1. Department of Epidemiology and Public Health, University College London, London, UK
  1. Correspondence to Professor J Wardle, Health Behaviour Research Centre, Department of Epidemiology and Public Health, Gower Street, University College London, London WC1E 6BT, UK; j.wardle{at}
  • Accepted 10 August 2009
  • Published Online First 30 August 2009


Objective: To investigate associations between weight status and body size perception in children in the UK.

Design: Cross-sectional survey.

Setting: School-based sample in the UK.

Participants: 399 children (205 boys, 194 girls) aged 7–9 years.

Main outcome measures: Perceived body size was assessed using a visual method (Children's Body Image Scale, matching to images representing body mass indexes (BMI) from 3rd to 97th percentiles) and verbal descriptors from ”too thin„ to ”too fat„. BMI (converted to BMI SD scores using UK data) was assessed and demographic information was recorded.

Results: Modest associations between actual and perceived body size were found with visual (r  =  0.43, p<0.001) and verbal (r  =  0.41, p<0.001) methods, but there was a consistent response bias towards underestimation. Using visual matching, most children (45%) underestimated their body size, with significantly greater underestimation (p<0.001) at higher BMI. A gender-by-weight group interaction (p = 0.001) showed that at lower weights girls were more accurate than boys, but at higher weights girls were less accurate. Using the verbal scale, the majority of children reported their body size as “just right” in all weight groups (52–73%), with no sex differences.

Conclusions: Children can estimate their body size using visual or verbal methods with some accuracy, but show greater underestimation at higher weights, especially in girls. These findings suggest that underestimation is more widespread than has been assumed, which has implications for health education among school-aged children.


  • Funding PEACHES is supported by Cancer Research UK (grant code C1418/A6124). The study sponsor had no role in the study design; in the collection, analysis and interpretation of data; in the writing of the report; or in the decision to submit the paper for publication.

  • Competing interests None.

  • Ethics approval Ethical approval for the study was granted by the University College London Committee on the Ethics of Non-NHS Human Research.

  • Patient consent Obtained.

  • Provenance and peer review Not commissioned; externally peer reviewed.

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