This study compared Autism diagnostic observation schedule (ADOS) algorithm scores of a sample of 26 children who were administered modules 1–3 of the ADOS with the scores obtained applying the revised ADOS algorithm proposed by Gotham et al. (
2007). Results of this application were inconsistent, yielding slightly more accurate results for module 1. New algorithm scores on modules 2 and 3 remained consistent with the original algorithm scores. The Mann–Whitney
U was applied to compare revised algorithm and clinical levels of social impairment to determine if significant differences were evident. Results of Mann–Whitney
U analyses were inconsistent and demonstrated less specificity for children with milder levels of social impairment. The revised algorithm demonstrated accuracy for the more severe autistic group.