Q. How different are the new standards from the old growth charts?
A. The new standards differ from any existing growth charts in a number of innovative ways. First the MGRS was designed to provide data that describe “how children should grow,” by including in the study’s selection criteria specific health behaviours that are consistent with current health promotion recommendations (e.g., breastfeeding norms, standard pediatric care, non-smoking requirements). This new approach is fundamentally different from that taken by the traditional descriptive references. By adopting a prescriptive approach, the protocol’s design went beyond an update of how children in presumably healthy populations grow at a specific time and place and explicitly recognizes the need for standards (i.e., devices that enable value judgments by incorporating norms or targets in their construction). Arguably, the current obesity epidemic in many developed countries would have been detectable earlier if a prescriptive international standard had been available 20 years ago.
Another key characteristic of the new standard is that it makes breastfeeding the biological “norm” and establishes the breastfed infant as the normative growth model. The previous reference was based on the growth of artificially-fed children.
The pooled sample from the 6 participating countries will allow the development of a truly international standard (in contrast to the previous international reference based on children from a single country) and reiterate the fact that child populations grow similarly across the world’s major regions when their needs for health and care are met.
These standards also include new innovative growth indicators beyond height and weight that are particularly useful for monitoring the increasing epidemic of childhood obesity, such as the skinfold thickness.
The study’s longitudinal nature will also allow the development of growth velocity standards. Health care providers will not have to wait until children cross an attained growth threshold to make the diagnosis of under-nutrition and overweight since velocity standards will enable the early identification of children in the process of becoming under- or over-nourished.
Lastly, the development of accompanying windows of achievement for six key motor development milestones will provide a unique link between physical growth and motor development.