Discrete-trial training (DTT) is a common method of instruction used in early intervention amongindividuals with autism spectrum disorder and related neurodevelopmental disorders and is an effective method of teaching different skills such as tacting, listener responding, and matching. Delivery of effective reinforcers is a key component of DTT. Although general recommendations have been made for effective reinforcement delivery in DTT, no review has synthesized the available research on the efficiency of various reinforcer parameters on efficiency of acquisition. The current systematic review assessed the efficiency of various reinforcer parameters on acquisition in DTT. Results were idiosyncratic, and a general paucity of repeated measures examining specific reinforcer parameters within and across studies was observed. In general, (1) maintaining high levels of treatment integrity, (2) delivery of tangible (i.e. leisure items) or edible reinforcers in comparison with contingent praise as a reinforcer, and (3) delivery of edible reinforcers in comparison with other topographies of reinforcement were the most successful reinforcer parameter manipulations and always resulted in more efficient skill acquisition. The results of this review provide clinicians with information regarding what reinforcer parameter manipulations may be more or less likely to support efficient acquisition. The present review also provides considerations and makes recommendations for future research.
