Purpose. The purpose of this study was to evaluate three psychophysical tests for the measurement of contrast sensitivity (CS) and disability glare (DG) at different luminance levels.
Methods. In 60 eyes of 60 individuals (group 1: 20 healthy eyes of young individuals; group 2: 20 healthy eyes of elderly subjects; group 3: 20 eyes with nuclear cataract), CS with best correction was measured twice with the Frankfurt-Freiburg Contrast and Acuity Test System (FF-CATS) and the Functional Acuity Contrast Test (FACT, 1.5 cycles per degree [cpd]) at 167 cd/m2 and 0.167 cd/m2, and with the Pelli-Robson Chart (PRC) at 100 cd/m2 with and without glare. Repeatability of test and retest, and discriminative ability between the different subgroups, were assessed for CS values.
Results. Maximum CS values varied across tests. In all groups, highest CS values were obtained with the photopic FF-CATS. For FACT scores at 1.5 cpd, there was a ceiling effect for young subjects. CS scores obtained with the PRC were the lowest. The PRC had the best test–retest repeatability of all tests. Under mesopic conditions with glare, reliability was generally lower; the FF-CATS had the highest repeatability of the mesopic tests. The FF-CATS discriminated best between the different groups for all conditions.
Conclusions. There are large discrepancies in the test results between CS testing methods, especially under different lighting conditions. Results from different CS tests are not interchangeable.
Department of Ophthalmology, Johann Wolfgang Goethe-University, Frankfurt am Main, Germany (JB, ET, TK), Department of Ophthalmology, University of Rochester Medical Center, Rochester, New York (JB), Department of Ophthalmology, Laboratory for Electrophysiology, University of Freiburg, Freiburg im Breisgau, Germany (MB), and College of Optometry (HFAK), Cologne, Germany (WW)
Presented in part at the 2003 annual meeting of the Association for Research in vision and Ophthalmology (ARVO), Fort Lauderdale, Florida; at the 2003 annual meeting of the German Society for Intraocular Lens Implantation and Refractive Surgery (DGII), Ludwigshafen, Germany; at the 2003 annual meeting of the German Ophthalmological Society (DOG) Berlin, Germany; at the 2004 Refractive Surgery Winter Meeting of the European Society of Cataract and Refractive Surgeons (ESCRS), Barcelona, Spain.
The authors have no proprietary interest in any programs or of the devices used in this study.
Received June 14, 2005; accepted February 14, 2006.