One Size Doesn't Fit All: Variability in Autistic Children's Response to Pivotal Response Treatment.

Pivotal Response Treatment (PRT) is a naturalistic developmental behavioral intervention designed to strengthen autistic children's social communication skills. Few studies have examined which children benefit the most from PRT and which characteristics are associated with meaningful progress. We analyzed data from 23 children with autism and significant language delay who had been randomized to receive PRT in a previously completed 24-week randomized controlled trial of parent training and clinician-delivered intervention. Participants were categorized as intervention responders and non-responders based on the demonstration of meaningful improvement (or lack thereof) in social communication using the MacArthur-Bates Communicative Development Inventories (MCDI) Reliable Change index scores and clinician determination based on review of language samples and the Clinical Global Impressions-Improvement Scale (CGI). Baseline child characteristics associated with being a responder were assessed. Sixteen participants were responders on the language sample, ten on the MCDI, and sixteen on the CGI. Nine were consistent responders across all three measures; six were consistent non-responders. Verbal ability at baseline was associated with being a responder across all measures. In our small sample, baseline verbal ability was associated with being a responder to PRT, though categorization as a responder differed somewhat based on outcome measure. Future research should explore responder profiles specifically in children who are nonspeaking to inform the development of more effective supports for this group.