Paraprofessional-Mediated ABA: Do Hours Matter Anyway?Studies show that more hours may not translate into better outcomes

A father and daughter draw with color pencils.

Applied behavior analysis (ABA) is an evidence-based intervention for young children with autism spectrum disorder (ASD). With the rates of ASD continuing to rise (Maenner et al., 2023) and all 50 states requiring behavioral health treatment for people with ASD (Straub et al., 2022) the demand for evidence-based intervention options for families continues to rise, particularly in community-based care. While not all people with ASD need or will even benefit from ABA, there is a proportion of the ASD population who will benefit significantly from ABA, particularly young children. However, for young children with ASD, there has been a myth in the field that families need to accept 30-40 hours per week of paraprofessional-delivered ABA, but is this number of hours necessary?

Empirical studies provide us with important information to consider

In 2015, Smith et al. conducted a study evaluating predictors of outcome for children with autism receiving Early Intensive Behavioral Intervention (EIBI), specifically they evaluated if social engagement and sensorimotor rituals  predicted treatment outcome when IQ was controlled for, social engagement predicted greater improvement in IQ and adaptive behavior. In their study, IQ at the time of intake predicted more gains for the children included. These researchers also evaluated if hours received predicted outcomes, finding no association. In fact, these authors stated:

Strikingly, although meta-analyses of EIBI and studies of other treatments have suggested that more hours are associated with larger gains for some participants, we found no such association. This finding could  indicate that contrary to the widespread belief of EIBI practitioners and researchers, treatment hours have little relation to outcome (p. 1279).

Two years after the release of this study, Tiura et al. (2017) conducted a study evaluating predictors of ABA treatment for children with ASD longitudinally. The results of their growth curve analysis revealed cognitive ability to be the greatest predictor of treatment outcome for children with ASD receiving ABA intervention, commensurate with the Smith et al. (2015) study. Following cognitive ability, age of entry predicted treatment outcome. Of importance these researchers found no predictive value of hours of ABA intervention received, “Our results also indicated that the number of treatment hours and parent education level did not significantly predict growth rates in any of the four developmental domains” (p. 196).

More recently, Rogers et al. (2021) conducted a randomized, multisite clinical trial evaluating two behavioral models of intervention for children with ASD, Early Start Denver Model (ESDM) and EIBI. Participants were randomly assigned to either model of intervention and from there were then delivered either 15 or 25 hours of the respective intervention. The population sample of this study was 87 children with ASD with a mean age of 23.4 months. Results of this study revealed neither intervention type (EIBI or ESDM) nor hours received was a main effect of the outcome variables which included autism severity, receptive language, expressive language, and non-verbal development. Findings from this study would indicate that 15 hours per week of intervention produces as significant an effect as 25 hours per week of intervention.

Ostrovsky et al. (2022) conducted a retrospective cohort analysis on 178 children with ASD with a mean age of 6 years, 9 months who all received ABA from the same provider. As with the other studies, while individuals made significant gains on the outcome measured used (Vineland-3), these gains were not a result of hours received. The mean hours received monthly were 27.53 by a paraprofessional, which translated to approximately 6.4 hours weekly of direct care. The results of this analysis are similar to those of a study conducted by Lotfizadeh et al. (2020) where groups receiving 10 hours per week and 5 hours per week of paraprofessional-delivered ABA both made significant improvements in outcome measures, with those in the 10 hours per week group faring better.

What can we take away from these recent studies? A clear result of the abovementioned research is the clear benefits of ABA intervention. However, while there has been a long-held belief that hours are a significant predictor of treatment outcome, it would appear that is just not the case. Some hours of ABA do make a difference, but it is difficult to know exactly what is the right amount of hours for a child with ASD. Based on these results it does appear children with ASD who receive 6 hours per week to 15 hours per week of ABA make significant and meaningful gains on their respective outcome measures and these gains are  commensurate with those who receive 25+ hours per week. With these empirical studies in mind, providers of ABA need to consider what is appropriate for families and their children with ASD. For clients who receive 6-15 hours per week of paraprofessional-mediated ABA, there are great benefits on top of receiving ABA which includes the ability to engage in more extracurricular activities and create more space for families to engage in family and community activities.


Lotfizadeh, A. D., Kazemi, E., Pompa-Craven, P., & Eldevik, S. (2020). Moderate Effects of Low-Intensity Behavioral Intervention. Behavior Modification, 44(1), 92–113. Read source document here

Maenner, M. J., Warren, Z., William, A., Amoakohene, E., Bakian, A., Bilder, D., Durkin, M. S., Fitzgerald, R., Furnier, S., Hughes, M., Ladd-Acosta, C., McArthur, D., Pas, E., Salinas, A., Vehorn, A., Williams, S., Esler, A., Grzybowski, A., Hall-Lande, J., … Shaw, K. A. (2023). Prevalence and Characteristics of Autism Spectrum Disorder Among Children Aged 8 Years—Autism and Developmental Disabilities Monitoring Network, 11
Sites, United States, 2020. MMWR. Surveillance Summaries, 72. Read source document here

Ostrovsky, A., Willa, M., Cho, T., Strandberg, M., Howard, S., & Davitian, C. (2022). Data-driven, client-centric applied behavior analysis treatment-dose optimization improves functional outcomes. World Journal of Pediatrics. Read source document here

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. Read source document here

Smith, T., Klorman, R., & Mruzek, D. W. (2015). Predicting Outcome of Community-Based Early Intensive Behavioral Intervention for Children with Autism. Journal of Abnormal Child Psychology, 43(7), 1271–1282. Read source document here

Straub, L., Bateman, B. T., Hernandez-Diaz, S., York, C., Lester, B., Wisner, K. L., McDougle, C. J., Pennell, P. B., Gray, K. J., Zhu, Y., Suarez, E. A., Mogun, H., & Huybrechts, K. F. (2022). Neurodevelopmental Disorders Among Publicly or Privately Insured Children in the United States. JAMA Psychiatry, 79(3), 232–242. Read source document here

Tiura, M., Kim, J., Detmers, D., & Baldi, H. (2017). Predictors of longitudinal ABA treatment outcomes for children with autism: A growth curve analysis. Research in Developmental Disabilities, 70, 185–197. Read source document here