Variability and Power to Detect Progression of Different Visual Field Patterns.

Abstract

PURPOSE\nTo compare the variability and ability to detect visual field progression of 24-2, central 12 locations of the 24-2 and 10-2 visual field (VF) tests in eyes with abnormal VFs.\n\n\nDESIGN\nRetrospective, multisite cohort.\n\n\nPARTICIPANTS\nA total of 52,806 24-2 and 11,966 10-2 VF tests from 7,307 eyes from the Glaucoma Research Network database were analyzed. Only eyes with ≥ 5 visits and ≥ 2 years of follow-up were included.\n\n\nMETHODS\nLinear regression models were used to calculate the rates of MD (Mean Deviation) change (slopes) while their residuals were used to assess variability across the entire MD range. Computer simulations (n=10,000) based upon real MD residuals of our sample were performed to estimate power to detect significant progression (P < 5%) at various rates of MD change.\n\n\nMAIN OUTCOME MEASURES\nTime required to detect progression.\n\n\nRESULTS\nFor all 3 patterns, the MD variability was highest within the -5 to -20 dB range and consistently lower with the 10-2 compared to 24-2 or Central 24-2. Overall, time to detect confirmed significant progression at 80% power was the lowest with 10-2 VF, with a decrease of 14.6% to 18.5% when compared to 24-2 and a decrease of 22.9% to 26.5% when compared to Central 24-2.\n\n\nCONCLUSION\nTime to detect central VF progression was reduced with 10-2 MD compared with 24-2 and C24-2 MD in glaucoma eyes in this large dataset, in part because 10-2 tests had lower variability. These findings contribute to current evidence of the potential value of 10-2 testing in the clinical management of glaucoma patients and in clinical trial design.