Effects of replacing text with speech output in an electronic mail application

An exploratory study of the advantages and disadvantages of speech output was conducted using an electronic mail program. All mail messages were in text, but program instructions were either in text or speech. Twenty subjects each used both versions of the program. Results showed that although speech output took longer, subjects could perform their tasks equally well with the text and speech output modes. Subjects interrupted the speech instructions 20% of the time, but only used the repeat key infrequently. Although the speech was rated as understandable, subjects showed a slight preference for the text version over the speech version. However. subjects who used the speech version before they used the text version rated the program as more interesting. more useful and more fun than subjects who used the ve r sions in the reverse order. Finally, subjects wrote down more task information (as notes) when they used the speech version, even though that information was in text form for both versions. Discussion focuses on the implications of these results for the use of speech output in an office environment.