WHO growth charts
In 2010, the WHO Growth Charts for Canada were released and were recommended as the standard growth charts for all Canadian children, to replace the CDC growths in use since 2000. The formatting of the 2010 charts was the result of a collaborative statement by the Dietitians of Canada, the Canadian Paediatric Society, the College of Family Physicians of Canada, and the Community Health Nurses of Canada.
A number of individuals and professional organizations, most notably the Canadian Pediatric Endocrine Group (CPEG), raised three concerns about the new WHO charts. In particular, CPEG felt that the loss of weight-for-age curves from ages 10–19 years in favor of a sole emphasis on the calculation of body-mass index (BMI) made the charts less useful for short-term clinical evaluation of weight gain or loss in growing children. Secondly, the inclusion of curves for the 0.1st and 99.9th centiles the 2010 charts raised the possibility of some physicians considering these extremes as the “normal range”, possibly delaying referral of children until they reached one of these extremes. Finally, the loss of the number of intermediate-centile (10th, 25th, 75th and 90th) curves on the 2010 charts made it potentially more difficult for clinicians to identify children who were “crossing centiles”.
CPEG therefore undertook to recreate the weight-for-age curves for children 10–19 years of age, using a
statistical method identical to that used by WHO, and including the majority of the data points in the WHO curves. Following discussions between the original collaborative group and CPEG, a consensus was achieved in March 2014, whereby two sets of growth charts would be released, both including the new weight-for-age curves developed by CPEG and differing only in the percentiles plotted:
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Set 1 uses centiles 3/15/50/85/97 (roughly −2/−1/0/+1/+2 standard deviations) on all charts and in addition includes the 99.9th centile (+3 SD) on the weight-for-length (0–24 months) and BMI-for-age (2–19 years) charts.
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Set 2 uses centiles 3/10/25/50/75/90/97 on all charts, substituting the 85th for the 90th centile and retaining the 99.9th centile on the weight-for-length (0–24 months) and BMI-for-age (2–19 years) charts. The 85th centile was used on the weight-for-length and BMI charts to correspond to the cut-off for obesity in adults.
English and French versions of both sets of growth charts are freely available for download at
www.whogrowthcharts.ca, as well as instructions for how they should be printed. For those individuals and electronic health-records companies wishing access to the LMS data used to plot the charts, these are also available by contacting
Dr. Daniel Metzger or
Dr. Atul Sharma.
BC Children’s Hospital is in the process of printing and instituting the use of the Set 2 consensus charts in the next few months. We encourage all clinicians seeing children in BC to switch to the revised
WHO Growth Charts for Canada, and measures are underway through the
BC Ministry of Health to ensure that this occurs on the public-health side as well.
Links to individual WHO Growth Charts for Canada, Set 2:
ZIP files containing all of the Set 2 charts are available:
A number of additional resources for the WHO Growth Charts for Canada:
See also our Anthropometric Calculators (tab above) for determining percentiles and Z-scores for the WHO Growth Charts for Canada, in addition to the CDC Growth Charts and a number of common syndromes.
Also take a look at the browser-based Growth Chart Plotter App (tab above) for plotting heights and weights for boys and girls ages 2 to 19 years, ideal for making growth charts for PowerPoint presentations.
