Accommodative Anomalies in a Sample of Black High School Students in South Africa

Accommodative anomalies cause asthenopia and affect student reading efficiency and academic performance. The aim of conducting this study was to determine the prevalence and distribution of accommodative anomalies (insufficiency, excess and infacility) in relation to demographic variables (sex, age, school grade level and study location).

Study participants comprised 1,211 children (481 male and 730 female), with age range 13-19 years. Visual functions evaluated included refractive error, accommodative amplitude, accuracy, facility and relative accommodation.

A total of 242 participants (20.2%) had accommodative anomalies. Prevalence estimates were; accommodative infacility 12.9% (95% confidence interval, CI, 10.9-14.7%), accommodative insufficiency 4.5% (95% CI 3.4-5.8%) and accommodative excess 2.8% (95% CI 1.9-3.8%). There were no significant differences based on sex, school grade level or study site, except in the prevalence of accommodative infacility, which was significantly higher in the younger grade level than the older (P=0.027).

The study fills a gap in the literature in providing data on predominantly black South African students. The prevalence estimates for accommodative insufficiency and excess found in the sample studied are relatively low, while that of accommodative infacility is high. Accommodative anomalies were not markedly associated with demographic variables except for the prevalence of accommodative infacility, which was significantly higher in the younger grade level than the older. Identification and referral are important steps towards diagnosis and treatment of accommodative anomalies. Future studies on differences in prevalence of accommodative anomalies among different racial populations will be relevant.