Thinking but not seeing: think-aloud for non-sighted users.

This paper discusses some of the methodological challenges that can be encountered when usability testing with visually impaired users. These include (1) the need for customized test environments, (2) the potential for audio interference between screen reader output and the moderator to participant dialogue, and (3) the difficulty for observers inexperienced in accessibility technology. In this paper we outline several techniques for dealing with these challenges, including some variations on traditional think-aloud techniques that are useful when a usability participant is using a screen reader.