2 years In between testing isn't a long time according to our opthamolagist. As dh has such poor eyesight and i don't it means our children need monitoring but every 2 yrs is fine
DD doesn't have bad eyes, but her paed opthamologist said 12 months as the longest break between visits. My opto has always said 12 months between check ups. a lot of growing and changing can happen in a year.