Hi, this is Tom, and in this episode I'm going to be going through growth charts,

and you can find notes at zero to finals.com slash growth charts and in the zero to finals pediatrics book,

and you can find flashcards and questions to train your knowledge at members.0.0.0.com. So let's jump straight in.

Growth charts are used to plot a child's weight, height and head circumference against the normal

distribution for their age and sex. Growth differs between boys and girls, so it's essential to use a sex-specific chart.

On a growth chart, the age is plotted on the X axis.

The weight, height or head circumference is plotted on the Y axis.

Each measurement is represented by a dot on the chart.

The curves on the chart represent centile lines,

showing the normal distribution of growth for healthy children.

Let's talk about centiles.

A centile, with cent, referring to 100,

indicates how a child's growth compares to the normal distribution for their age and sex.

The 50th centile represents the mean or average,

with 50% of children being smaller and 50% of

children being larger than the 50th centile.

A child on the 1st centile is smaller than 99% of their peers.

A child on the 91st centile is taller or heavier than 91% of their peers.

The pattern over time is more important than a single measurement.

A child whose weight or height is consistently tracking the 9th centile is not a cause for concern,

as the ninth centile appears to be normal for them. However, a child who's dropped from the 91st

to the ninth centile suggests faltering growth and this requires assessment.

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