Visual Acuity Testing in Pre-School Aged Children – What Can Be Expected?

Melinda Whitton, BAppSc(Orth) (Hons)

Three hundred and sixty pre-school aged children underwent orthoptic screening as part of The Outreach Programme run by The Orthoptic Department of Sydney Eye Hospital. The children were screened at Kindergartens and Child Care Centres in the inner city. Of the 360 children screened 353 (98%) cooperated with monocular Sheridan Gardiner (SG) visual acuity testing at 6 metres. Of the children participating in visual acuity testing 79.9% managed SG linear testing, with 20.1% of the children being tested with SG singles. There was a significant difference in the age of children who completed the SG singles versus SG linear method testing. SG singles testing was required more often with the younger children. The average visual acuity score for SG singles assessment was 6/6 part, with the majority of children achieving 6/6; whereas for SG linear assessment the average score was 6/9 plus, with the majority of children achieving 6/9. It was found that irrespective of the visual acuity test method used, older children achieved slightly better visual acuity results than younger children. It was also found that irrespective of the child’s age SG singles testing produced better visual acuity results than SG linear. Reduced visual acuity was noted in 9.8% of children with SG singles testing and 2.5% with SG linear.