Measuring everyday visual discrimination in visually impaired children with the Sonksen Picture Guide to visual function

The Sonksen Picture Guide to Visual Function (SPGVF) assesses a person's ability to discriminate pictures of everyday objects. Sonksen added the SPGVF to tests of visual acuity, because real objects, miniatures, and pictures are the main learning medium for young children. In earlier studies correlations have been found between visual acuity and responses to the SPGVF. However, to date no studies have used visually impaired children. In the study reported here, the associations between performance on the SPGVF task, visual acuity and contrast sensitivity were investigated. Participants were 17 visually impaired and 29 children without disabilities, 4--6 years of age. The results showed that visual acuity was more important for picture recognition than contrast sensitivity. Contrast thresholds < 3.33% implied that not all SPGVF-pictures could be recognized. The visually impaired children in the current study showed shorter mean identification distances than the normally sighted children in the original Sonksen and Macrae study.