In two earlier posts I talked about studies that showed that word recognition is 17% more accurate and sentence comprehension is 5% faster with ClearType. Given these findings we should certainly expect that that there are reading benefits for ClearType when reading extended text. But what about other common office tasks that involve reading, but are more complicated than just straight-forward reading? Andrew Dillon and his colleagues at the University of Texas’ School of Information investigated both of these questions.
Participants in the extended duration reading study read five screens full of 12 point Arial text rendered with ClearType and five screens with 12 point Arial black & white rendered text. All of the expected controls were used so, for instance, half the participants saw a particular article rendered with ClearType, and the other half saw the same article rendered in black & white.
As expected from the earlier findings, people were reliably faster with ClearType without any differences in accuracy of visual fatigue. Participants read for 9 minutes and 9 seconds on average with ClearType, and 9 minutes and 39 seconds with black & white rendering, a reading speed advantage of about 5%. The reading speed for each of the five screens of text was also faster with ClearType.
More interesting was the participants’ performance on a spreadsheet scanning task. In the spreadsheet scanning task participants were asked to perform a task that involved more navigation around the spreadsheet than would typically occur while reading a regular page of text. In the below example, participants were asked how many books are acceptable for an age 4-7 reading level and cost $21. To answer this question, participants need to look at each row of text and count how many rows meet both conditions.
Dillon and colleagues found that people performed the tasks reliably faster when the spreadsheet was rendered in ClearType without any differences in accuracy or visual fatigue. Participants took on average 4 minutes and 40 seconds to complete tasks with ClearType compared to 5 minutes and 4 seconds with black & white rendering, a difference of about 8%.
ClearType not only improves reading speed for traditional page reading, but also improves the efficiency for completing any task that involves recognizing words or numbers.
Dillon, A., Kleinman, L., Choi, G. O., & Bias, R. (2006). Visual search and reading tasks using ClearType and regular displays: two experiments. CHI ’06: Proceedings of the SIGCHI conference on Human Factors in computing systems, 503-511.