B. L. Chalfonte, R. S. Fish, and R. E. Kraut. Expressive richness: a comparison of speech and text as media for revision. In CHI ’91: Proceedings of the SIGCHI conference on Human factors in computing systems, pages 21–26, New York, NY, USA, 1991. ACM. [PDF]
This paper presents an experimental comparison of two modalities sharing annotations on a shared document. The authors designed this experiment under the assumption given by previous research that richer, more informal, and more interactive media should be better suited for ahndling collaborative tasks.
The authors designed an experiment for comparing subject reviewing a paper using text and speech annotations. They found that participant were more likely to make local annotations in the written modality (spelling and grammar changes) and more likely to make global annotations in the speech modality (structure, missing a fundamental point, project status, etc.).
They defined a nice metric: the index of self-correction, the number of times an annotation was corrected before the final submission. They found that speech annotations were more likely to be corrected than written annotations. They also found that speech allowed for non-verbal communication that made communication richer.
From the analysis it appeared that speech was superior because it was more expressive, and because it placed fewer cognitive demands on a communicator. However, this study did not focus in revealing the advantages or trade-offs of annotations in different modalities.