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Applied Behavior Analysis as an Intervention for Individuals with Autism: Reflections on 35 years of Evolution

It is difficult to find the words that best describe the evolution of autism treatment over the past 35 years. The science of applied behavior analysis (ABA) has changed substantially over the last 35 years. In 1980, autism was considered to be a low incidence disorder that was not as well understood as it is in 2015. In 1980, individuals with autism were routinely diagnosed after the age of six. Specialized programs were few and far between. Effective treatments were in the infant stages of their development. Applied behavior analysis itself was a young science, and the application of it to autism was even younger. Lovaas’ revolutionary study demonstrating the power of applied behavior analysis in changing the behaviors of individuals with autism was still seven years from publication (Lovaas, 1987). Early intervention was not yet a reality for this population of learners, given the late initial diagnosis. Behavioral intervention was available in some specialized settings, though few people with ASD had access to them. In some ways, behavioral interventions lacked nuance. While behaviors could be changed, they were not yet interpreted, analyzed, and treated with function in mind. Treatment still relied on the use of aversive procedures to a much greater extent than they do in 2015. The assessment of generality, maintenance, and social validity were in their earliest stages.

Child with autism spectrum disorder learns clock and hours, teacher during ABA therapy class

Looking at the evolution of the field through the lens of time’s passage, it may be helpful to see it as a function of the impact of technology on assessment, treatment, and the evaluation of outcomes. We are broadly defining technology to include the identification of new ways to understand and treat autism spectrum disorder. New technology has influenced intervention dramatically in diagnosis, the assessment and treatment of challenging behaviors, skill acquisition, and data collection.

As mentioned above, diagnosis in 1980 occurred most often at the end of preschool or in the early elementary years. Diagnosis was generally done through informal assessment and parental interview. Many individuals who were not “classically” autistic were not understood to be on the spectrum. Furthermore, intervention was a formidable task when individuals were not diagnosed as toddlers. The majority of learners were non-vocal, lacked learning readiness skills that had failed to develop in the preschool years, and had well-established repertoires of automatically reinforced (self-stimulatory) behaviors.

Over the last 20 years, there has been a radical change in our ability to detect autism in young children. Diagnostic procedures have evolved to include direct observational methods of assessment, enabling diagnosis to be considerably more objective. The ADOS (Lord, Lisi, Lambrecht et al., 2000) is the gold standard measure, and it brilliantly includes the assessment of pivotal deficits that are notable at young ages, including joint attention. Furthermore, outreach to the pediatrician community has resulted in routine screenings of autism red flags at most well-baby visits. Many doctors now administer tools such as the M-CHAT (Robins, 2008) at the 18 month visit, screening for early signs of autism, including the absence of pointing, joint attention, responsiveness to name, and babbling. Parents also have instantaneous access to information on the web about warning signs, leading more parents to identify those signs in their children.

In addition, the Center for Disease Control has altered the prevalence rates, and it is now clear that this is not a low incidence disorder. As a result of all of these changes, and with the increase in information available on the web, awareness of autism is exceptionally high. The media routinely covers autism stories, and autism interventions are frequently cropping up and being touted as effective. This can be a challenge for parents seeking information on effective treatment, but it is much easier to access information about autism in 2015 than it was in 1980.

For diagnosed children who are receiving services, the greatest changes may have occurred in the realm of the assessment and treatment of challenging behaviors. In 1980, there was still a focus on behavior modification in the absence of behavioral assessment. The technology of functional analysis, first outlined in the seminal article published in 1982, was revolutionary (Iwata, Dorsey, et al., 1982). Challenging behaviors are now evaluated in terms of the functions they serve for the learners. Is this individual garnering attention, effectively escaping from tasks, successfully obtaining desired items? In other words, how is this (aberrant) behavior working for the individual; what maintains it in their behavioral repertoire? The assessment of function enables treatment to focus on preventing the occurrence of the behavior through a variety of antecedent strategies and replacing the aberrant behavior with appropriate replacement behaviors.

There has also been a tremendous change in the array of skill acquisition approaches. In 1980, most individuals with ASD were taught using discrete trial instruction (DTI; e.g., Lovaas, 1981). This sequenced form of instruction enabled individuals with autism to learn concrete skills in an effective way. DTI remains an essential component of educational interventions for autism, and is still heavily relied on to efficiently teach many skills. However, the field has also developed many additional procedures to target initiation skills, including incidental teaching, pivotal response training, and natural environment training (e.g., Fenske, Krantz, & McClannahan, 1991; Hart & Risley, 1982; Koegel & Koegel, 2012; Koegel, O’Dell, & Koegel, 1987; Sundberg & Partington, 1998, 1999). All of these methods teach in more informal and more naturalistic contexts. The addition of naturalistic teaching procedures has expanded the focus of intervention and the identified goals for individual learners, and has resulted in improved generalization of skills. In addition, there has been an increased value placed on the development of functional skills (e.g., Cooper, Heron, & Heward, 200). Behavior analysts focus on the development of skills that will increase the individual’s access to reinforcers, community integration, and quality of life. In 1980, training was fairly simple and straight forward, as competent staff had only a few skills to master in order to effectively teach. Today, the training of staff is a complex endeavor, and it is a moving target. As the field improves and identifies new effective techniques, staff must be trained in these state-of-the art interventions.

One excellent development over the last 20 years has been the credentialing of behavior analysts. The Behavior Analyst Certification Board ( certifies individuals at the paraprofessional level (Registered Behavior Technician or RBT), the assistant level (Board Certified Assistant Behavior Analyst or BCaBA, and behavior analyst level, including BCBA (master’s level) and BCBA-D (doctoral level). There have been steady increases in the rigorous standards set for certification, and the credentials have become fully recognized as the designation associated with competence.

Data collection has also been revolutionized with new technological options. Hand held data devices and a multitude of apps allow for instantaneous data collection during instruction. The iPad has been used in novel ways to present instructional material, track progress, and fill the communicative needs of individuals with ASD.

The evolution has been astonishing. With the advent of new diagnostic methods and early detection, individuals are able to begin effective treatment as toddlers. This has dramatically altered the course of the disorder for many individuals with ASD. Furthermore, individuals receive more diverse and effective instruction, as the number of evidence-based procedures has grown. Challenging behaviors are now routinely addressed through function-based assessments and interventions tailored to those functions. Functional assessment has become individualized in the same ways that treatment has been tailored to individual service recipients. This has led to the development of more effective behavior intervention plans and a far reduced need for interventions relying on aversive procedures. Finally, data collection strategies have been tremendously expanded with the development of new devices and new apps.

As we look to the future, it is with great anticipation and optimism. Autism is routinely detected at young ages. Increasingly, effective treatment is available to individuals diagnosed with ASD. Nuanced applications of the science of applied behavior analysis have led to assessment and intervention procedures that are more individualized and more effective. The science continues to evolve more precise methods and more precise data collection strategies to track progress and outcomes. The credentialing of behavior analysts continues to become more rigorous, and the BCBA credential is being recognized not only as useful, but also as essential. The field as a whole continues to add to the literature in crucially important areas including the assessment of generalization, social validity, and quality of life. It is impossible to know just what will define the field 35 years from now, but the momentum is high and the future is very bright.

Rita Gardner, MPH, LABA, BCBA, is CEO-Elect, Mary Jane Weiss, PhD, BCBA-D, is Executive Director of Research, and Frank L. Bird, MEd, BCBA, is Chief Clinical Officer at Melmark. The mission of Melmark is to serve children, adults and their families affected by a broad range of intellectual disabilities. With service divisions in Berwyn, Pennsylvania and Andover, Massachusetts, we provide evidence-based educational, vocational, clinical, residential, healthcare and rehabilitative services, personally designed for each individual in a safe environment of warmth, care and respect. For more information, please visit and


Cooper, J. O., Heron, T. E., & Heward, W. L. (2007). Applied Behavior Analysis. 2nd edition. Upper Saddle River, New Jersey: Prentice Hall.

Fenske, E. C., Krantz, P. J., & McClannahan, L. E. (2001). Incidental teaching: A not-so-discrete-trial teaching procedure. In C. Maurice, G. Green, & R. M. Foxx (Eds.), Making a difference: Behavioral intervention for autism. Austin, Texas: Pro-Ed.

Hart, B. M., & Risley, T. R. (1982). How to use incidental teaching for elaborating language. Austin, TX: Pro-Ed.

Iwata, B., Dorsey, M. F., Slifer, K. J., Bauman, K. E, & Richman, G. S. (1982). Toward a functional analysis of self-injury. Journal of Applied Behavior Analysis, 2, 3-20.

Koegel, R. L. O’Dell, M. C., & Koegel, L. K. (1987). A natural language teaching paradigm for nonverbal autistic children. Journal of Autism and Developmental Disorders, 17, 187-200.

Koegel, R. L. & Koegel, L. K. (2012). The Pivotal Response Treatment Pocket Guide. Baltimore: Brookes Publishing Company.

Lord C., Risi S., Lambrecht L., et al. (2000). The Autism Diagnostic Observation Schedule–Generic: a standard measure of social and communication deficits associated with the spectrum of autism. Journal of Autism and Developmental Disorders, 30, 205–223.

Lovaas, O. I. (1987). Behavioral treatment and normal educational and intellectual functioning in young autistic children. Journal of Consulting and Clinical Psychology, 55, 3-9.

Lovaas, O. I. (1981). Teaching developmentally disabled children: The ME book. Baltimore: University Park Press.

Robins, D. L. (2008). Screening for autism spectrum disorders in primary care settings. Autism: The International Journal of Science and Practice, 12 (5), 537-556.

Sundberg, M. L. & Partington, J. W. (1998). Teaching language to children with autism or other developmental disabilities. Pleasant Hill, CA: Behavior Analysts, Inc.

Sundberg, M. L. & Partington, J. W. (1999). The need for both DT and NE training for children with autism. In P. M. Ghezzi, W. L. Williams, & J. E. Carr (Eds.), Autism: Behavior Analytic Approaches. Reno, NV: Context Press.

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