I have to admit now to having a lifelong fascination with vision screening. My father was an optometrist and he gave us a thorough vision screening every year. I was enchanted by the atmosphere of his office – the darkness and the gruesome looking lens. My problem was that I had perfect eyesight – but I wanted to have glasses. Eventually, he gave me a pair with clear lens to keep me happy. I would wear them then and he would tell me ‘sparkle a little Mary’ and I was happy to identify with the geek in Pride and Prejudice, when my sister and friends all wanted to be Elizabeth.
It only dawned on me gradually that my own children were not getting this kind of a service. This is because there is considerable variation in the vision screening protocols used to assess children in western countries, and no widespread screening in developing countries. In Sweden, for example, visual acuity is measured in pre-school age children and again at seven and 10 years of age (Kvarnstrom 2001). In the UK, routine vision screening is recommended for four- to five-year-old children only (PHE 2017).
My father’s ideal was that children should receive an eye examination every year, or more frequently if specific problems or risk factors exist. Unfortunately, parents and educators often incorrectly assume that if a child passes a school screening, then there is no vision problem. However, many school vision screenings only test for distance visual acuity. A child who can see 20/20 can still have a vision problem. In reality, the vision skills needed for successful reading and learning are much more complex (American Optometry Association, www.aoa.org). Visual related academic tasks largely involve near tasks (47%), distance tasks (29%), distance to near tasks (15%), and computer tasks (9%) (Narayanasamy, Vincent, Sampson, & Wood, 2016).
In New Zealand, children are screened for amblyopia (lazy eye) at the age of four, and for distance acuity at the age of 10-11 (B4 school check, 2015). Colour vision testing was dropped from NZ screening program in 2016. Near vision is not tested, thought this is relevant to classroom performance (Hopkins, Sampson, Hendicott, & Wood, 2013). There is evidence that hyperopia is often missed with current screening (Renner, 2017).