Parents and carers need to play close attention to any signs that a child may not be seeing well.

In general, the earlier a problem is detected, the easier it is to put right. If a child shows any of the following signs a full sight test with a qualified optician can set your mind at rest:

• the child closes one eye to look at objects
• the child tilts the head when looking at objects
• the child cannot judge depth
• the child may bump into objects - particularly on one side

Many opticians offer sight testing for pre-school children, and three years is often a good age to do this while the visual system is still developing. However, obvious problems e.g. a clear squint or an inability to recognise toys and faces should be checked out earlier.

To find out more about lazy eyes, see our dedicated guide.