title: Understanding disparities among diagnostic technologies in glaucoma.
abstract: OBJECTIVE
  To investigate causes of disagreement among 3 glaucoma diagnostic techniques: standard automated achromatic perimetry (SAP), the multifocal visual evoked potential technique (mfVEP), and optical coherence tomography (OCT).
  
  
  METHODS
  In a prospective cross-sectional study, 138 eyes of 69 patients with glaucomatous optic neuropathy were tested using SAP, the mfVEP, and OCT. Eyes with the worse and better mean deviations (MDs) were analyzed separately. If the results of 2 tests were consistent for the presence of an abnormality in the same topographic site, that abnormality was considered a true glaucoma defect. If a third test missed that abnormality (false-negative result), the reasons for disparity were investigated.
  
  
  RESULTS
  Eyes with worse MD (mean [SD], -6.8 [8.0] dB) had better agreements among tests than did eyes with better MD (-2.5 [3.5] dB, P<.01). For the 94 of 138 hemifields with abnormalities of the more advanced eyes, the 3 tests were consistent in showing the same hemifield abnormality in 50 hemifields (53%), and at least 2 tests were abnormal in 65 of the 94 hemifields (69%). The potential explanations for the false-negative results fell into 2 general categories: inherent limitations of each technique to detect distinct features of glaucoma and individual variability and the distribution of normative values used to define statistically significant abnormalities.
  
  
  CONCLUSIONS
  All the cases of disparity could be explained by known limitations of each technique and interindividual variability, suggesting that the agreement among diagnostic tests may be better than summary statistics suggest and that disagreements between tests do not indicate discordance in the structure-function relationship.
authors: Einhorn Clinical Research Center, The New York Eye and Ear Infirmary, and Department of Ophthalmology, New York University School of Medicine, New York, New York 10003, USA. demoraesmd@gmail.com
authors: Carlos Gustavo V
authors: CG
authors: De Moraes
authors: Jeffrey M
authors: JM
authors: Liebmann
authors: Robert
authors: R
authors: Ritch
authors: Donald C
authors: DC
authors: Hood
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001369:Axons / Q000473:pathology; D003430:Cross-Sectional Studies; D005074:Evoked Potentials, Visual; D005188:False Negative Reactions; D005260:Female; D005901:Glaucoma / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009898:Optic Disk / Q000473:pathology; D009901:Optic Nerve Diseases / Q000175:diagnosis*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015203:Reproducibility of Results; D012165:Retinal Ganglion Cells / Q000473:pathology; D041623:Tomography, Optical Coherence; D014786:Vision Disorders / Q000503:physiopathology; D058609:Visual Field Tests; D014794:Visual Fields / Q000502:physiology; D055815:Young Adult