Support/Funding for the study: This study was fully supported by Children's Health Foundation in London, ON, Canada.
Evaluating Canadian children: WHO, NHANES or what?
Article first published online: 19 MAR 2013
© 2013 The Authors. Journal of Paediatrics and Child Health © 2013 Paediatrics and Child Health Division (Royal Australasian College of Physicians)
Journal of Paediatrics and Child Health
Volume 49, Issue 4, pages 282–290, April 2013
How to Cite
Yasin, A. and Filler, G. (2013), Evaluating Canadian children: WHO, NHANES or what?. Journal of Paediatrics and Child Health, 49: 282–290. doi: 10.1111/jpc.12152
Conflict of interest: None declared.
- Issue published online: 11 APR 2013
- Article first published online: 19 MAR 2013
- Manuscript Accepted: 2 SEP 2012
- Children's Health Foundation
- Bland–Altman test;
- height z-score;
- weight z-score;
The 2006 World Health Organization (WHO) growth charts have been widely adopted by Canadian dieticians for growth monitoring of Canadian children rather than the National Health and Nutrition Examination Survey (NHANES III) reference data. It has been unclear as to which is the most appropriate.
We calculated height and weight z-scores of 3086 consecutive patients (1530 female, 49.6%) aged 0–5 years, attending outpatient clinics at a single tertiary care centre using reference data of the latest NHANES survey and the 2006 WHO growth charts. To address age dependency, data were stratified into age groups. Gender dependency was also investigated.
Using NHANES III reference intervals, medians of both height z-score (+0.24) and weight z-score (+0.32) were significantly non-zero. The WHO growth charts yielded medians of height z-score (−0.15) and weight z-score (+0.36) respectively, also significantly non-zero. When comparing both reference populations for the entire cohort, Canadian children had significantly different height z-scores whereas weight z-scores did not differ. Age classification revealed a significant age dependency with NHANES III charts yielding higher weight z-scores for up to 8 months and lower z-scores from 8 to 26 months. No significant differences were observed for older than 26 months. Throughout, height z-scores were significantly higher with NHANES III charts across all age groups, with a degree of overestimation higher in younger boys than older ones.
Our results reveal substantial differences between both reference populations and thus interpretation needs to be done with caution, especially when labelling results as abnormal.