We conducted a meta-analysis of 31 studies, spanning 30 years, utilizing the WCST in participants with autism. We calculated Cohen's d effect sizes for four measures of performance: sets completed, perseveration, failure-to-maintain-set, and non-perseverative errors. The average weighted effect size ranged from 0.30 to 0.74 for each measure, all…

Three questions regarding the use of sign language as an alternative communication system for nonverbal autistic children are examined. Data on effects on speech, the upper limits of sign acquisition, and effects on adaptive function are discussed. (Author/CL)