Estimating exclusion: a tool to help designers

An exclusion audit assesses how inclusive a product or service is. This is useful for comparing designs and identifying points for improvement. In an exclusion audit, the designer or usability expert identifies the demands a product places on the user‟s capabilities and enters these into an exclusion calculator. This software then estimates the proportion of the adult British population who would be excluded from using the product because their capabilities do not meet these demands. This paper describes research on improving the exclusion calculator based on a recent reanalysis of the calculator‟s underlying dataset. This enabled the capabilities to be broken down into more specific sub-categories or “demand types”. An experiment investigated the use of these demand types in the context of an exclusion audit. It found that participants could determine the demand type of an action consistently, in the majority of cases. This approach was adopted in a redesign of the calculator, described in this paper.