A systematic review of vision screening tests for the detection of amblyopia

Objective. To review the test characteristics and the quality of evidence r egarding available screening tests for the detection of amblyopia in presch ool-aged children to help primary care practitioners select a screening str ategy. Design. Systematic review of published studies. Data Sources. The MEDLINE database was searched from 1966 through January 1 999 using a broad and inclusive strategy. A total of 9551 citations were id entified. Study Selection. All studies that compared the results of commercially avai lable screening tests in preschool-aged children to ophthalmologic examinat ion. Data Extraction. The setting of the study, the age of the population, the t ype of screening test, criteria for a positive screen, criteria for the oph thalmologic 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 tes t characteristics of 3 screening tests. None of these studies were performe d in a primary care setting. Each study used different criteria for failure of the ophthalmologic examination. None of the studies measured observer o r test reliability. Conclusions. Few high-quality data exist regarding the performance of presc hool 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.