Effects of intervention intensity on skill acquisition and task persistence in children with Down syndrome

Background Modifying intensity is one approach to tailoring intervention to meet the needs of learners with developmental disabilities. This study examined the effects of varying intensity levels of a behaviour analytic intervention on the efficiency of acquisition and task persistence in young children with Down syndrome. Methods Using adapted alternating treatment designs, three children were taught expressive language targets when three aspects of the dose of intervention intensity varied: number of opportunities, spacing of opportunities and session duration. Results Children acquired targets faster in conditions in which the spacing of opportunities was shorter than conditions in which the spacing was longer. Two children showed greater expression of positive affect in moderate levels of intensity. Children showed idiosyncratic differences in off‐task behaviour. Discussion This research suggests that pacing of opportunities may be an important for understanding acquisition outcomes in a behaviour analytic approach to intervention for communication among young children with Down syndrome.