Date of Award

May 2017

Degree Type


Degree Name

Master of Science



First Advisor

Tiffany Kodak

Committee Members

Jeffrey Tiger, Valerie Volkert, Tiffany Kodak


ASD, Problem Behavior, Skill Acquisition, Task Interspersal


Task interspersal (TI) is a procedural variation of discrete trial training that has been implemented with children with autism spectrum disorder (ASD) to facilitate the acquisition of novel skills, and may reduce problem behavior during instruction. The literature shows equivocal results regarding the efficiency of TI, but there is limited literature indicating the effects on level of problem behavior. The current study extended the literature on TI by comparing the efficacy and efficiency of varying TI ratios implemented in early intervention practices with children with ASD and related disorders on acquisition and levels problem behavior. The four ratios of mastered to acquisition stimuli included 75% mastered to 25% acquisition, 50% mastered to 50% acquisition, 25% mastered to 75% acquisition, and 0% mastered to 100% acquisition. An adapted alternating treatments design was implemented to compare the number of stimuli mastered, and the level of problem behavior. A condition was considered efficacious if at least one stimulus was mastered and problem behavior was reduced by 50% of the pre-test level. The condition that resulted in the most stimuli mastered in the fewest trial presentations was considered the most efficient intervention procedure. The results showed that the 0%M/100%A condition was the most efficient intervention procedure for all four participants. Results were inconsistent on the efficacy of the procedures regarding levels of problem behavior.