ASSESSMENT OF THE ABILITY OF METHODS OF MEASURING CATARACT TO DETECT CLINICALLY SIGNIFICANT CHANGE

We present the use of a ratio of a clinically significant change/95% t olerance limits (CSC/TL) as a method of assessing the ability of vario us methods to measure changes in cataract severity. The indirect metho d which we used, ETDRS visual acuity (logMAR), had a CSC/TL value <1 i ndicating that it could not detect a change of 1 LOCS III unit while c omputerized image analysis systems had CSC/TL values >1 indicating tha t they would be able to detect changes finer than 1 LOCS III unit. We recommend the use of CSC/TL to evaluate methods in clinical studies.