Objective: To review the test characteristics and the quality of evidence regarding available screening tests for the detection of amblyopia in preschool-aged children to help primary care practitioners select a screening strategy.
Design: Systematic review of published studies.
Data sources: The MEDLINE database was searched from 1966 through January 1999 using a broad and inclusive strategy. A total of 9551 citations were identified.
Study selection: All studies that compared the results of commercially available screening tests in preschool-aged children to ophthalmologic examination.
Data extraction: The setting of the study, the age of the population, the type of screening test, criteria for a positive screen, criteria for the ophthalmologic examination, test characteristics, and measures of reliability were abstracted by 2 reviewers for each selected study.
Data synthesis: Four eligible articles were identified that studied the test characteristics of 3 screening tests. None of these studies were performed in a primary care setting. Each study used different criteria for failure of the ophthalmologic examination. None of the studies measured observer or test reliability.
Conclusions: Few high-quality data exist regarding the performance of preschool vision screening. Important future work should include the development of a consensus gold standard ophthalmologic examination and evaluation of screening tests in the primary care setting.