Effects of pivotal response treatment on reciprocal vocal contingency in a randomized controlled trial of children with autism spectrum disorder
Authors: McDaniel Jena , Yoder Paul , Crandall Madison , Millan Maria Estefania , Ardel Christina Mich , Gengoux Grace W , Hardan Antonio Y 
Published: February 2020

A pivotal response treatment package consisting of clinician-delivered and parent-implemented strategies was recently found to be effective in improving language and social communication deficits in children with autism spectrum disorder. Reciprocal vocal contingency, an automated measure of vocal reciprocity, may provide stronger and complementary evidence of the effects of the pivotal response treatment package. Reciprocal vocal contingency is derived through an automated process from daylong audio samples from the child’s natural environment. Therefore, reciprocal vocal contingency is at lower risk for detection bias than parent report and brief parent–child interaction measures. Although differences were non-significant at baseline and after 12 weeks of intervention for the 48 children with autism spectrum disorder who were randomly assigned to the pivotal response treatment package or a delayed treatment control group, the pivotal response treatment package group had higher ranked reciprocal vocal contingency scores than the control group after 24 weeks ( U = 125, p = .04). These findings are consistent with results from parent report and parent–child interaction measures obtained during the trial. The participants in the pivotal response treatment package exhibited greater vocal responsiveness to adult vocal responses to their vocalizations than the control group. Findings support the effectiveness of the pivotal response treatment package on vocal reciprocity of children with autism spectrum disorder, which may be a pivotal skill for language development. Lay abstract A recent randomized controlled trial found that children with autism spectrum disorder who received a pivotal response treatment package showed improved language and social communication skills following the intervention. The pivotal response treatment package includes clinician-delivered and parent-implemented strategies. Reciprocal vocal contingency is an automated measure of vocal reciprocity derived from daylong audio samples from the child’s natural environment. It may provide stronger and complementary evidence of the effects of the pivotal response treatment package because it is at lower risk for detection bias than parent report and brief parent–child interaction measures. The current study compared reciprocal vocal contingency for 24 children with autism spectrum disorder in the pivotal response treatment package group and 24 children with autism spectrum disorder in the control group. The pivotal response treatment package group received 24 weeks of the pivotal response treatment package intervention. The control group received their usual intervention services during that time. The groups did not differ in reciprocal vocal contingency when the intervention started or after 12 weeks of intervention. However, after 24 weeks the pivotal response treatment package group had higher ranked reciprocal vocal contingency scores than the control group. These findings are consistent with results from parent report and parent–child interaction measures obtained during the trial. The participants in the pivotal response treatment package exhibited greater vocal responsiveness to adult vocal responses to their vocalizations than the control group. Findings support the effectiveness of the pivotal response treatment package on vocal reciprocity of children with autism spectrum disorder, which may be a pivotal skill for language development.