Methods of Clinical Cataract Grading: Two Systems Compared-Reply

Abstract

In Reply. —I wish to express my appreciation to Dr Sparrow for his kind comments about the LOCS II Cataract Classification System. I have no substantial disagreement with any of the points he raises except to point out that the number of useful features in any cataract classification system is often set more by the uniqueness and recognizability of the feature than the will of the grader. For example, should a group of graders desire to use all of the features in the Oxford Classification System, they might find that some of the less conspicuous features cannot be graded consistently by the same or different graders. The low κ values discourage them from using such features rather than their simple disinclination to use them. Early in the development of the LOCS II system, we were sure that we could reproducibly grade nuclear color on a six-step scale; we gradually