Rogers, S. J., Yoder, P., Estes, A., Warren, Z., McEachin, J., Munson, J., Rocha, M., Greenson, J., Wallace, L., Gardner, E., Dawson, G., Sugar, C. A., Hellemann, G., & Whelan, F. (2021). A multisite randomized controlled trial comparing the effects of intervention intensity and intervention style on outcomes for young children with autism. Journal of the American Academy of Child & Adolescent Psychiatry, 60(6), 710-722. https://doi.org/10.1016/j.jaac.2020.06.013

Reviewed by Jenna Budge, LSW, BCBA and Robert H. LaRue, PhD, BCBA-D
Rutgers, The State University of New Jersey

Why research this topic?

Research Synopses - Psuchological, Educational and Therapeutic InterventionsImprovements in screening and detection of developmental disabilities and autism spectrum disorder (ASD) in young children heighten the need for information regarding the benefits of early intervention. Implementing evidence-based practices at a younger age can significantly improve communication and adaptive behavior in individuals diagnosed with ASD (e.g., Pickles, et al., 2020; Smith et al., 2010). The need to better understand what works in early intervention programs, as well as the intensity of treatment (hours per week), would allow families and practitioners to advocate for and provide interventions that may improve outcomes for their child or student.

What did the researchers do?

The authors conducted an intent-to-treat, single-blind randomized clinical trial (RCT) at three university programs between 2013 and 2019. An intent-to-treat study refers to when the results of a study are analyzed based on the group participants were randomly assigned to, regardless of the treatment they actually received. Eighty-seven toddlers between the ages of 12-30 months diagnosed with ASD participated in the investigation. Participants were from three different sites and were randomly assigned to one of four groups: Early Intensive Behavioral Intervention (EIBI) for 15 hours/week, EIBI for 25 hours/week, Early Start Denver Model (ESDM) for 15 hours/week, or ESDM for 25 hours/week. Treatments were delivered over 12 months in homes or childcare settings by trained investigators using manualized approaches for both EIBI and ESDM. Sessions were usually 1.5 to 2.5 hours in length. Both manualized treatments were individualized to meet the learning needs of the participants. The authors used multiple evidence-based assessments and screeners to evaluate autism symptom severity, expressive communication, nonverbal abilities, and receptive language over 24 months. Assessments were conducted at the time of enrollment, at six months (mid intervention), 12 months (end of intervention), and 24 months (follow-up). Naïve observers were used to compare the effects the two interventions and two levels of intensity.

What did the researchers find?

The authors reported that all four groups showed improvement across the domains. However, there were no significant differences between treatment type (EIBI v. ESDM) or treatment intensity (15 v. 25 hours) on expressive communication, nonverbal abilities, and receptive language. The authors also found no relationship between the initial degree of developmental delay and autism severity on child outcomes in either intervention condition. Caregivers across all groups reported high treatment satisfaction.

What are the strengths and limitations of the study? What do the results mean?

This study is one of the few systematic comparisons between intervention intensity and improvement in autism symptoms. Its strengths include the random assignment of participants to groups and the naivety of coders to group assignment to improve objectivity.

Practitioners and caregivers should be cautious about drawing conclusions from this study. Although results suggest that there are minimal differences across treatment type and treatment intensity, this could be attributed to the age range of the participants. Participants in the current study were between the ages of 12 months and 2.5 years, so limited gains with minimal differentiation between groups might be expected, especially as intervention effects were monitored for only a year post-intervention. This is particularly important as participants in the Lovaas EIBI study that serves as the benchmark comparison (e.g., Lovaas, 1987) referenced in the study were between the ages of 2.5 and 5 years. In addition, the Lovaas model these results are compared to had a longer duration of intervention (i.e., several years). Future studies might evaluate older age ranges (e.g., two to five) delivered for a longer period of time for a more apt comparison.

It could also be argued that the ABA groups in the current investigation were provided with sub-threshold intervention for what would be considered high-quality EIBI. Given the relatively low levels of staff training and supervision, the lack of robust treatment effects is not surprising. In other words, the study compared ESDM to a lower quality implementation of EIBI. While the study did not find statistically significant differences across sites for the number of hours of intervention, the authors specifically noted that their findings do not contradict the National Academy of Sciences (2001) recommendation of 20 hours per week of intervention. Specifically, 25 hours of intervention was found to be more efficacious than 15 hours of intervention for reducing the severity of the core autism symptoms at one of the sites.

References

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

Pickles, A., Le Couteur, A., Leadbitter, K., Salomone, E., Cole-Fletcher, R., Tobin, H., Gammer, I., Lowry, J., Vamvakas, G., Byford, S., Aldred, C., Slonims, V., McConachie, H., Howlin, P., Parr, J. R., Charman, T., & Green, J. (2016). Parent-mediated social communication therapy for young children with autism (PACT): Long-term follow-up of a randomised controlled trial. Lancet, 388 (10059), 2501-2509.

Smith, T., Groen, A., & Wynn, J. (2000). Randomized trial of intensive early intervention for children with pervasive developmental disorder. American Journal of Mental Retardation, 105, 269-285.

Citation for this article:

Budge, J., & LaRue, R. (2022). Research Synopsis: A multisite randomized controlled trial comparing the effects of intervention intensity and intervention style on outcomes for young children with autism. Science in Autism Treatment, 19(9).

Related ASAT Articles:

Related Research Synopses:

Print Friendly, PDF & Email