Growth monitoring is an essential part of assessing children’s health care.  Tracking how a child is growing can provide awareness of nutritional issues or other health problems. Growth charts are used to compare an individual child’s growth to what is considered normal or healthy. Unfortunately, the growth charts used in New Zealand are adapted from those used elsewhere around the world. They do not reflect the diversity found in the New Zealand population.

Laura McCrae found that the data used to create the World Health Organisation Growth Standards came from Brazil, Ghana, India, Norway, Oman and the USA. She also found that children born in different areas around the world often differed from the standards laid out by the World Health Organisation. Data from children born in Belgium and Norway differed significantly from the WHO Standards, with height, weight, head circumference, and BMI all outside their ‘normal’ range.

During the Summer of Research, Laura undertook a project to personalise growth assessment in New Zealand by analysing the population specific data from sources such as Growing Up in New Zealand and Plunket. The generalisability of the data was measured in comparison to relevant census data, with special attention given to socio-economic and ethnic participation. Laura then used multiple different methods of data modelling to create graphs like the one pictured below, which shows customised growth percentiles by age.

Using a combination of these models and further research, Laura will soon be able to create New Zealand specific growth charts. One of the conclusions of her research over the summer period was the need for customised growth charts for individual children. The purpose of the Precision Driven Health initiative is to help find innovative ways to provide personalised treatment. Healthcare should not have a ‘one size fits all’ approach, and Laura’s research reinforces this fact.

While using global standards to track growth may have been the best we could do a few years ago, modern technology allows us to be far more precise. New Zealand has been recording health information electronically for over 10 years now, which puts us in the unique position of being able to tailor information like these growth charts to individual patients. The ethnic diversity of a country like New Zealand makes this data even more valuable. Precise growth charts and other health data specific to separate ethnicities will be extremely beneficial for our population.

Laura McCrae is among a group of students who took part in the summer of research programme funded by Precision Driven Health. This month we are featuring a blog series examining these projects. While at an elementary stage and considered to be a ‘proof of concept’, these projects offer fresh insights into what the world of healthcare will look like when precision medicine is fully implemented.