Evaluating the Use of a Backward Chaining Procedure to Teach Young Autistic Children Multiple Step Requesting Using AAC

This study evaluated the use of a time delay with a least-to-most prompting hierarchy and backward chaining, in the acquisition of a multi-step mand sequence for three young autistic children, who also use an augmentative and alternative communication (AAC) system. The AAC system involved the application Linggo™ and an iPad Mini ® , which functioned as a speech-generating device. The study used a changing criterion, within a reversal design, across a three phased task analysis. Each phase constituted a change in criterion, with a return to baseline between each phase. Two of the participants learned to complete all steps of the task analysis with relatively quick acquisition rates. The third participant only learned to perform the first step of the chain, though his absences and subsequent attrition may have contributed to that outcome. This study adds to the existing literature on the instruction of multi-step manding with an AAC for young autistic children, by adding support for the use of time delay, least-to-most prompting, and backwards chaining. Limitations, clinical and research implications are also discussed.