Behaviorist methods of treating autism which often focus on manipulating the contingencies of behaviors using so-called artificial reinforcers have lead some researchers and parents to criticize their inflexibility and one-size-fits-all approach to intervention (e.g., Fay, W.H. 1980, Prizant, Barry 1982).
We present a randomized control trial of the effectiveness of a therapy program based on the Developmental Individualized Relationship-Based (DIR) model of autism intervention that is distinguished from typical behaviorist programs by (1) employing no artificial reinforcement, and (2) solely using play-based social interaction as a vehicle for treatment.
56 children ages 2;0 – 4;11 were recruited from the Toronto area. Children were previously diagnosed with an ASD and the diagnoses were confirmed via ADOS and ADI-r. Children were randomly selected for either treatment through the DIR-based program (DTx) or a community-based treatment program (CTx). Children in the DTx group met with therapists for 2 hours each week to receive hands-on training in the DIR-based method. Participants were assessed both prior to the onset of treatment and 12 months post treatment using a modified version of the Child Behavior Rating Scale (mCBRS) video-taped rating scale of 5 behaviors thought to be pivotal for development including attention to activity, enjoyment in interaction, cooperation, involvement, and initiation of joint attention (Mahoney, 1998). In addition, a standard language assessment was also administered to participants to determine whether the increase in social interaction skills was accompanied by an increase in language skills.
The results indicate that children in the DTx group displayed significantly more of the sorts of pivotal interaction behaviors that are associated with healthy development than did the community treatment group. Moreover, analysis of the scores obtained from the language assessments also revealed that the DTx group made significantly greater gains in the standardized language scores over the course of 12 months than did the CTx group. The associated effect sizes are clinically significant or near clinically significant (Wolf 1986) ranging from .47 to 1.01. These results are encouraging since they suggest that children are improving not only in basic interaction behaviors, but also in language skills as measured by standard language assessments. Finally, a regression analysis confirms the hypothesis that performance on the mCBRS was a significant predictor of change in language scores for this group of children diagnosed with an ASD.
Children in the DTx group showed significantly greater enjoyment in interactions with their parents, were significantly more attentive and involved in interactions with their parents, initiated more joint attentional frames, and made significantly greater language gains. Along with the regression analysis, which suggests that children's performance on the mCBRS is a significant predictor of language change, these results support the hypothesis that children with autism can in fact learn through play-based social interaction (as do typical children) without the apparent need for so-called artificial reinforcers.