The Effects of Response Format and Other Variables on Comparisons of Digital and Dial Displays

Abstract

We compared dial and digital clock displays to determine which could be read faster by 25 young adults. The influence of several variables on differences in response speed between the 2 display types was examined. These variables included response format (times expressed as minutes before the hour, minutes after the hour, or simple reading of hour and minute values), interval difficulty (times displayed in 5-min intervals or in intervals not divisible by 5), and the quadrant from which displayed times were selected. In general, digital displays led to faster responses than did dial displays. However, several combinations of the other variables, particularly those using the before-the-hour response format, effectively eliminated the superiority of digital displays. We suggest that in designing displays requiring such a response format, designers should not assume that a digital display is necessarily the best choice, especially if other factors encourage the selection of a dial display.