Touch screen user interfaces for older subjects: effect of the targets number and the two hands use

This study investigated the optimal numbers of blocks and tactile targets for touch screen user interfaces intended for use by all (reference and older population). Three independent variables (number of targets, number of interaction blocks on the touch screen and number of hands used) were studied in our experiment. Huge amount of data were stored. In this paper, we will only report statistical analyses on two variables: Time needed to Realize the Test and Error Rate. Each variable will be analyzed in two times: for the whole population (reference and older) and for the comparison between these two populations.