The use of ICT tools is broadly extended among people with intellectual disabilities and also, to a lesser degree, the use of learning tools including learning games. Although the use of learning games is widely accepted due to its high engagement capacity, there are few studies that analyze its usability for people with intellectual disabilities. This work presents an evaluation of the impact of adding an autonomous playing mode on the usability of a learning game designed to aid the training of oral skills in people with Down syndrome. A study in which the effectiveness, efficiency and user satisfaction of a learning game are compared when the system is used with different degrees of teacher supervision is carried out. A learning game originally designed to train oral competencies for people with Down syndrome in a teacher supervised scenario is adapted to allow its autonomous use, by including a module that provides the automatic assessment of oral productions. The use of the tool is thus compared in three different scenarios: a supervised environment, autonomous use, and laboratory use with multiple users working in parallel. The different usability evaluation instruments used reveal that, although there are no differences in the degree of engagement, there may be important differences regarding session performance: the quality of the audios is lower in the laboratory sessions and the number of errors increases in the autonomous sessions. We conclude that, although the autonomous use of learning games by users with intellectual disabilities is possible, and this can lead to considerable savings in human resources, if the feedback provided by the game is not comparable with that provided by the teacher, performance may drop considerably although the degree of engagement is maintained.
