This paper describes an attempt to develop a fuzzy data aggregation technique for analyzing data collected during a groupware usability study. We show the formal parallelism between the decision making problem and that of ranking alternatives in a usability study. This equivalence allows using a combination of Decision under Uncertainty and Multi-Criteria Decision Making (MCDM) techniques for ranking alternatives for developing an approach for ranking alternatives within a usability study. The effectiveness of such approach is then illustrated with experimental data gathered during a usability study conducted by the Ambient Technology Group in Middlesex University.