To the Editor.
—We read with interest the recent article by Katz and Sommer1 on age-adjusted variability of automated visual fields. The authors analyzed the variability of threshold-measuring computerized perimetry in 26 eyes from a nonrandom normal population, with each eye testedthree times over a period of 18 months. They concluded that the variation was highly dependent on the age of the individual, being larger in older subjects.We have recently reported a prospective analysis of intratest, intertest, and interindividual variability of randomly selected normal individuals2 using the same instrument and test program as that used by Katz and Sommer. We did not report the effect of age on intertest variability in any detail, and since our results do not entirely agree with those of Katz and Sommer, we present them here.
Subjects and Methods.
—Our analyses were performed on one eye from each of
Heijl A, Lindgren G, Olsson J. Perimetric Threshold Variability and Age. Arch Ophthalmol. 1988;106(4):450-451. doi:10.1001/archopht.1988.01060130492014