Statistical stereo-acuity norms in Saudi children

PURPOSE: This paper aimed to study the norms for clinical stereo-acuity in Saudi children aged between six and 12 years and to determine the 95 per cent confidence limits for stereo-acuity thresholds in this group of subjects. METHODS: A total of 1,383 normal subjects (883 male and 500 female) aged between six and 12 years participated in this study. External examination, cover test, visual history and visual acuity were assessed for each subject prior to Titmus stereo-acuity measurement. RESULTS: The range of stereo-acuities attained by subjects for each age was 40 to 100 seconds of arc. The average stereo-acuity threshold showed an inverse (improved) relationship with the age of the subjects. CONCLUSION: This study indicates that not all children achieve the normal adult stereo-acuity of 40 seconds of arc by the age of 12 years. However, approximately 99 per cent of all children up to and above the age of six years achieve stereo-acuity thresholds of 80 seconds of arc or better. These results should serve as a guide when assessing the binocular vision status of school-aged children in Saudi Arabia