DoCEG: COVID-lockdown effects?

We are now two years and four visits into the Dynamics of Childhood Eye Growth (DoCEG) study at Hatch Ride School. Every six months, we learn a little more about eye growth, and we now have enough data to start seeing patterns.

What have we found so far?

The measurement we care about most is axial length, which is how long the eyeball is from front to back. Axial length is one of the best signs of whether a child is likely to become short-sighted (myopic), and how quickly that might progress.

Most of what we're seeing lines up well with previous research. Other studies have reported eyes growing by roughly 0.1–0.21mm a year on average — this is about the same thickness as 1–2 sheets of paper. Our own numbers show an average growth of 0.16 mm, which sits right in the middle of that range.

Each data point represents the length of one eye from each child. Year groups as of Jun 2026.

One thing stood out

Not every year group followed the pattern we expected, though. Children in Year 2 at our last visit (who have now entered Year 3) had eyes that were, on average, a bit longer than the overall trend would predict, and their eyes grew faster than any other group (0.22 mm / year). The outgoing Year 6 children, by contrast, grew more slowly than average (0.11 mm / year), which isn't surprising, since eye growth is known to naturally slow down as children get closer to their teens.

Data points represent the average eye length of the year group. Year groups as of June 2026.

So what could be causing this difference in year groups?

It is too early to tell yet, but we are looking into whether the difference could be linked to COVID-lockdown. Children who were in Year 2 at our last visit would have been roughly 6–18 months old when the UK went into lockdown in March 2020 — right in the middle of a period when the visual system develops very rapidly. It's possible that spending less time outdoors during those crucial early months could have had some effect on how their eyes have grown since. There's already research linking COVID lockdowns to faster myopia progression in children more generally, but this is usually put down to more screen time and less time outside.

But “possible” isn't the same as proven. This is just one school and one possible explanation among many. It might turn out to be a real pandemic-related effect, or it might just be the kind of natural variation you'd expect to see between any two groups of children. We don't know yet — which is exactly why studies like this need to keep running. It’s also why it’s a good idea to keep up-to-date with your visits to the optician.

What's next

We are very grateful for all the children who take part, visit after visit! We will be returning to Hatch Ride again in November, and every visit adds more of the picture — not just biometry, but retinal imaging and other measures that should help us understand not just if some children's eyes grow differently, but also why.