Evaluating the Benefit of Highlighting Key Words in Captions for People who are Deaf or Hard of Hearing

Recent research has investigated automatic methods for identifying how important each word in a text is for the overall message, in the context of people who are Deaf and Hard of Hearing (DHH) viewing video with captions. We examine whether DHH users report benefits from visual highlighting of important words in video captions. In formative interview and prototype studies, users indicated a preference for underlining of 5%-15% of words in a caption text to indicate that they are important, and they expressed an interest for such text markup in the context of educational lecture videos. In a subsequent user study, 30 DHH participants viewed lecture videos in two forms: with and without such visual markup. Users indicated that the videos with captions containing highlighted words were easier to read and follow, with lower perceived task-load ratings, compared to the videos without highlighting. This study motivates future research on caption highlighting in online educational videos, and it provides a foundation for how to evaluate the efficacy of such systems with users.