Howlin, P., Magiati, I., & Charman, T. (2009). Systematic review of early intensive behavioral interventions for children with autism. American Association on Intellectual and Developmental Disabilities, 114, 23-41.
Reviewed by Amy Hansford, MS
Rutgers University
Why research this topic?
Among the most thoroughly evaluated programs is early intensive home-based behavioral intervention (EIBI), which begins at the age of four years or younger and involves 20-40 hours per week of intervention for two or more years. This review analyzed the outcomes of controlled EIBI studies.
What did the researchers do?
Thirteen studies were included in the review, including Lovaas’ (1987) original study and its follow up in 1993 by McEachin, Smith, and Lovaas. Each study had a comparison group varying in treatment. Treatments included parent-directed, low intensity EIBI, eclectic, special autism school, or a mixture of interventions. The mean duration for both EIBI and comparison groups was approximately 27.4 months (except for Lovaas’ study) and follow up which lasted two to six years. Children in the EIBI groups received significantly more hours of intervention (29.8) per week than children in comparison groups that did not receive EIBI (19.1).
What did the researchers find?
Overall, the researchers found that there were positive results for all EIBI groups, including a few individuals being placed in a regular classroom setting. IQ change was the only measure reported in every study, showing significant differences in nine of the eleven studies. Six studies reported an increase in verbal and nonverbal IQ outcomes. A few studies reported on levels of problem behavior and severity of autistic symptoms.
What are the strengths and limitations of the study? What do the results mean?
This review indicated that EIBI may be effective for some, but not all children with autism. The greatest gains may occur in the first 12 months of treatment. However, the researchers described many shortcomings in studies on EIBI. One limitation is that the only variable consistently reported across all studies was IQ. Because other measures varied across studies, it was not possible to assess children’s overall functioning after intervention. Also, it was often unclear how much treatment children actually received in the studies. Future research should include more randomized controlled studies incorporating family functioning and better assessments. Research should also compare EIBI to other autism interventions.