Methods and Strategies: Applied Behavioral Analysis & Discrete Trial Training
Applied Behavioral Analysis & Discrete Trial Training
Applied behavior analysis (ABA)∗ comprises interventions obtained from the principles of behavior analysis designed to analyze and change behavior in a precisely measurable and accountable manner. It employs strategies based on scientific principles of behavior that are designed to build socially useful repertoires and reduce problematic ones. The defining assumption of ABA is that behavior is learned and controlled by contingencies within the environment.
The ABA model has been used very effectively to change behavior in many diverse areas. The model has been especially effective in developing, implementing, and evaluating instructional programs for children and youth with autism. The literature shows that, for this group of students, instruction can be presented in a variety of ways (incidental teaching, discrete trial, natural language paradigm, etc.) and still be considered a behavior analysis approach. Many behavior analysts, however, advocate that instruction for individuals with autism should be presented in a “discrete trial” format. A discrete trial consists of four parts:
• An instruction stated as concisely as possible, for example, “Come here,” versus “I
want you to come here, please.” The request may be presented with a prompt
(assistance) that is reduced systematically as the child responds more independently.
• A response from the child that may take several forms including successful
completion (a correct response), partial success, noncompliance, or unresponsiveness.
The latter two would be considered incorrect responses.
• A consequence provided by the practitioner (classroom teaching staff, parent,
therapist) that corresponds to the child’s response. Correct responses enable the child to access some highly preferred item as a reinforcer, for example, verbal praise, toy play, tickling, edibles, sensory stimulation, etc. Incorrect responses are followed by feedback indication the child’s response was inaccurate. Such feedback may include saying “No,” and removing materials and attention for one to two seconds before repeating the instruction.
• An inter-trial interval. This refers to the teacher pausing briefly after providing a
consequence and before starting the next trial. An inter-trial interval helps to ensure
that each trial is discrete from the next trial.
Teaching staff using this model may provide instruction initially when seated at a table with the child directly across from them. This may occur to help establish student responsiveness to the teacher. However, discrete trial instruction can be provided in any situation in and out of the classroom setting.
Specific Strategies include:
• Targeted skills are broken down into small attainable tasks.
• Targeted skills are based upon the child’s individual needs (teaching sessions may
cover a wide range of developmentally appropriate behaviors including imitation,
receptive/expressive discriminations, communication, peer interaction and play, as
well a challenging behaviors such as tantrums and noncompliance).
• Skills are developed in a hierarchical manner.
• Highly preferred materials are identified systematically and are available as
reinforcers throughout the day.
• Skills are encouraged by reinforcing desired behaviors systematically, and ignoring,
redirecting, or discouraging challenging behaviors.
• Complex skills are taught through the use of chaining.
• Mastery of a skill is based on a numerical criterion, for example, a percentage.
• Progress is closely monitored by continuously collecting and analyzing child
• Changes in instruction occur as a function of child performance data.
• Newly mastered skills are reviewed to ensure retention.
• Newly mastered skills are adapted to ensure the generalization of skills across
persons, materials, and locations.
• Skills are practiced in progressively less structured settings and more natural
situations to ensure generalization across increasingly variable situations; for
example, children may answer questions in a group setting while taking turns with
∗ Applied Behavior Analysis is sometimes used interchangeably with “Lovaas Therapy.” The groundbreaking work of Dr. O. Ivar Lovaas, one of the earliest pioneers in the behavioral treatment of young children with autism, is one example of the use of Applied Behavior Analysis.