Vision screening of preschool children: evaluating the past, looking toward the future.

Vision problems of preschool children are detectable with a comprehensive eye examination; however, it is estimated that only 14% of children below the age of 6 years receive an eye examination. Screening is advocated as a cost-effective alternative to identify children in need of further vision care. Thirty-four states recommend or require vision screening of preschool children. Although laws and guidelines exist, only 21% of preschool children are actually screened for vision problems. There is little agreement concerning the best screening methods, and no validated, highly effective model for screening vision of preschool children. Newer screening tests have been designed specifically for preschool populations, and can be administered by lay screeners. Many have not been validated. Several are recommended by states or organizations without convincing scientific evidence of their effectiveness. This paper summarizes current laws and guidelines for preschool vision screening in the United States, reviews advantages and disadvantages of several test procedures, and provides recommendations for developing future preschool vision screening programs.