M Schulzer1. 1. Department of Medicine, University of British Columbia, Vancouver, Canada.
Abstract
BACKGROUND: Despite strictly defined criteria for visual field progression in the ongoing Normal-tension Glaucoma Study, the authors noted a surprisingly large number of patients reaching the endpoint. Traditional methods could not be used to check the diagnostic accuracy of their criteria, because no "gold standard" was established for distinguishing true change from physiologic long-term fluctuation. METHODS: The authors developed a statistical method based on the results of duplicate tests for progression in their subjects. This method allowed the authors to assess the sensitivity, specificity, and predictive values of their diagnostic criterion. It also estimated the true incidence of progression and provided standard errors for the estimates. RESULTS: The authors found that their original strict criteria for progression, based on duplicate testing, produced false calls of progression 57% of the time. By raising the requirement for deterioration and by repeating the entire sequence of duplicate testing once more, the authors have successfully reduced the rate of false calls to 2%. CONCLUSION: Accuracy in recognizing progression is improved by not accepting small changes as evidence of progression and by confirming the findings on repeat testing.
RCT Entities:
BACKGROUND: Despite strictly defined criteria for visual field progression in the ongoing Normal-tension Glaucoma Study, the authors noted a surprisingly large number of patients reaching the endpoint. Traditional methods could not be used to check the diagnostic accuracy of their criteria, because no "gold standard" was established for distinguishing true change from physiologic long-term fluctuation. METHODS: The authors developed a statistical method based on the results of duplicate tests for progression in their subjects. This method allowed the authors to assess the sensitivity, specificity, and predictive values of their diagnostic criterion. It also estimated the true incidence of progression and provided standard errors for the estimates. RESULTS: The authors found that their original strict criteria for progression, based on duplicate testing, produced false calls of progression 57% of the time. By raising the requirement for deterioration and by repeating the entire sequence of duplicate testing once more, the authors have successfully reduced the rate of false calls to 2%. CONCLUSION: Accuracy in recognizing progression is improved by not accepting small changes as evidence of progression and by confirming the findings on repeat testing.
Authors: John L Keltner; Chris A Johnson; Richard A Levine; Juanjuan Fan; Kimberly E Cello; Michael A Kass; Mae O Gordon Journal: Arch Ophthalmol Date: 2005-09
Authors: Felipe A Medeiros; Robert N Weinreb; Grant Moore; Jeffrey M Liebmann; Christopher A Girkin; Linda M Zangwill Journal: Ophthalmology Date: 2012-01-21 Impact factor: 12.079
Authors: D S Kamal; A C Viswanathan; D F Garway-Heath; R A Hitchings; D Poinoosawmy; C Bunce Journal: Br J Ophthalmol Date: 1999-03 Impact factor: 4.638
Authors: Angelo P Tanna; Donald L Budenz; Jagadeesh Bandi; William J Feuer; Robert M Feldman; Leon W Herndon; Douglas J Rhee; Julia Whiteside-de Vos; Joyce Huang; Douglas R Anderson Journal: Ophthalmology Date: 2011-12-02 Impact factor: 12.079