User reconfigurations of the de Boer rating scale for discomfort glare

Abstract

This study evaluated the de Boer rating scale for discomfort glare. The aim was to determine if the scale was effective in rating discomfort glare and, if not, what modifications are necessary to improve the scale. The hypothesis was that the de Boer scale was not optimal for rating the true psychological effect of discomfort glare by American observers. Two tasks were performed by each subject. The first task was an ordering of the verbal descriptors, in which the subject ordered the five verbal descriptors from the scale in the order they thought the scale should run. The second task was to number the scale they created. The results indicate that (1) there is a problem with the way the de Boer scale is numbered, and (2) some of the verbal descriptors are confusing and can lead to improper scaling of glare. These results are consistent with the hypothesis that the de Boer scale is not the optimal scale for rating discomfort glare by American observers, and research on an improved scale is necessary.