Draft Key Questions
Disposition of Comments Report
Archived: This report is greater than 3 years old. Findings may be used for research purposes, but should not be considered current.
People using assistive technology may not be able to fully access information in these files. For additional assistance, please contact us.
Open-angle glaucoma (OAG) is the most common form of progressive optic neuropathy, and it is estimated that more than half of those who have glaucoma are undiagnosed. The objective of this review was to assess the effect of screening for OAG. We also summarized the accuracy of diagnostic tests.
We searched MEDLINE®, Embase, LILACS, and CENTRAL through October 6, 2011. We searched MEDLINE and CENTRAL (March 2, 2011) and screened an existing database to identify relevant systematic reviews.
We included studies of adult asymptomatic participants in general or high-risk populations. We included randomized controlled trials, quasi-randomized controlled trials, cohort studies, and case control studies. For diagnostic test accuracy, we included case control studies, designs in which tests were performed on all participants, and designs in which participants were randomized to one test. We included the outcomes of visual impairment, intraocular pressure, optic nerve damage, visual field progression, and harms as well as sensitivity and specificity of tests. For studies and systematic reviews, two reviewers independently assessed search results according to the inclusion criteria. One reviewer abstracted information and completed risk-of-bias assessment, and this was verified by a second reviewer.
We excluded 167 of the 169 citations found in the search for systematic reviews. One systematic review evaluated the diagnostic accuracy of screening tests for OAG. A second review evaluated the effect of screening programs on the prevention of optic nerve damage. We identified 4,960 studies, of which 83 studies addressing the accuracy of screening tests were eligible. The sensitivity of standard automated perimetry (SAP) was higher than Goldmann tonometry, similar to the Heidelberg retina tomograph (HRT), and lower than disc photos or frequency doubling technology (FDT) visual field testing. The specificity of SAP was higher than disc photos and FDT, similar to HRT, and lower than Goldmann tonometry. Some comparisons of tests could not be performed due to variability in populations and reported thresholds. We identified no other studies.
We did not identify any systematic review or study that provided evidence for direct or indirect links between glaucoma screening and visual field loss, visual impairment, optic nerve damage, intraocular pressure, or patient-reported outcomes. Early treatment is important in determining the indirect chain of evidence for screening; the treatment of glaucoma is addressed in the report Treatment for Glaucoma: Comparative Effectiveness. There have been improvements in screening devices, yet there is limited evidence on the effects of screening for OAG.