Discrete trial training
Discrete trial training (DTT) is a technique used by practitioners of applied behavior analysis (ABA) that was developed by Ivar Lovaas at the University of California, Los Angeles (UCLA). DTT uses mass instruction and reinforcers that create clear contingencies to shape new skills. Often employed as an early intensive behavioral intervention (EIBI) for up to 25–40 hours per week for autistic children, the technique relies on the use of prompts, modeling, and positive reinforcement strategies to facilitate the child's learning. It previously used aversives to punish unwanted behaviors. DTT has also been referred to as the "Lovaas/UCLA model", "rapid motor imitation antecedent", "listener responding", "errorless learning", and "mass trials".
Many intensive behavioral interventions rely heavily on discrete trial teaching (DTT) methods, which use stimulus-response-reward techniques to teach foundational skills such as attention, compliance, and imitation. While DTT is effective for teaching foundational skills such as attention, compliance, and imitation, children may struggle to apply these skills to real-world settings. These students are also taught with naturalistic teaching procedures to help generalize these skills. In functional assessment, a common technique, a teacher formulates a clear description of a problem behavior, identifies antecedents, consequences, and other environmental factors that influence and maintain the behavior, develops hypotheses about what occasions and maintains the behavior, and collects observations to support the hypotheses. A few more-comprehensive ABA programs use multiple assessment and intervention methods individually and dynamically.
ABA-based techniques have demonstrated effectiveness in several controlled studies: children have been shown to make sustained gains in academic performance, adaptive behavior, and language, with outcomes significantly better than control groups. A 2009 review of educational interventions for children, whose mean age was six years or less at intake, found that the higher-quality studies all assessed ABA, that ABA is well-established and no other educational treatment is considered probably efficacious, and that intensive ABA treatment, carried out by trained therapists, is demonstrated effective in enhancing global functioning in preschool children. These gains may be complicated by initial IQ.
A 2008 evidence-based review of comprehensive treatment approaches found that ABA is well established for improving intellectual performance of young children with ASD. A 2009 comprehensive synthesis of early intensive behavioral intervention (EIBI), a form of ABA treatment, found that EIBI produces strong effects, suggesting that it can be effective for some children with autism; it also found that the large effects might be an artifact of comparison groups with treatments that have yet to be empirically validated, and that no comparisons between EIBI and other widely recognized treatment programs have been published.
A 2009 systematic review came to the same principal conclusion that EIBI is effective for some but not all children, with wide variability in response to treatment; it also suggested that any gains are likely to be greatest in the first year of intervention. A 2009 meta-analysis concluded that EIBI has a large effect on full-scale intelligence and a moderate effect on adaptive behavior. However, a 2009 systematic review and meta-analysis found that applied behavior intervention (ABI), another name for EIBI, did not significantly improve outcomes compared with standard care of preschool children with ASD in the areas of cognitive outcome, expressive language, receptive language, and adaptive behavior. ABA is cost effective for administrators.
A multi-site randomized control trial study in 2023 compared 25 hours per week of discrete trial training (DTT) to 2.5 to 20 hours per week of JASPER therapy, a naturalistic developmental behavioral intervention. Progress was identified with both approaches: 45% of participants gained typical spoken language, and the children with lower receptive language skills who received DTT showed larger gains in the long-term.
Recently, behavior analysts have built comprehensive models of child development (see Behavior analysis of child development) to generate models for prevention as well as treatment for autism.