A Multisite Randomized Controlled Trial Comparing the Effects of Intervention Intensity and Intervention Style on Outcomes for Young Children With Autism.

This randomized, multisite, intent-to-treat study tested the effects of two levels of treatment intensity (number of hours) and two treatment styles on progress of young children with autism spectrum disorder (ASD). We predicted that initial severity of developmental delay or autism symptoms would moderate the effects of intensity and style on progress in four domains: autism symptom severity, expressive communication, receptive language, and nonverbal ability.