EPIDEMIOLOGY Frequency-Doubling Threshold Perimetry in Predicting Glaucoma in a Population-Based Study The Beijing Eye Study

Objective: To determine the predictive value of fre-quency-doubling threshold perimetry for glaucoma in a population-based study. Methods: The Beijing Eye Study, a population-based study on subjects 40 years or older, included an oph-thalmic examination with fundus photography and fre-quency-doubling threshold perimetry. Glaucoma was de-fined by a glaucomatous optic disc appearance. Results: The study population consisted of 4349 sub-jects (8615 eyes). Among 207 glaucomatous eyes (2.4%), 74 (35.7%) did not show any abnormality on frequency-doubling threshold perimetry, suggesting a diagnostic sen-sitivity of 64.3%. In the total study population, a visual field defect was found in 905 eyes (10.5%). In 133 (14.7%) of these eyes, a glaucomatous appearance of the opti