When it comes to toddlers with autism, more intervention hours are not always better

A multi-site study led by researchers from UC Davis Health has found that while early intervention measures for children with autism spectrum disorder were important, there was little difference between treatment types, or between the different timings of 15 hours a week or 25 hours a week. 

Researchers explored two prominent early intervention models for autism, comparing developmental and symptom improvements in toddlers with autism who received one year of one-on-one intervention sessions using either the Early Intensive Behavioral Intervention (EIBI) or Early Start Denver Model (ESDM). 

“When parents receive the first diagnosis, they typically ask: What kind of treatment should I seek and for how many hours per week?” Professor Sally J. Rogers, lead author said. 

“As clinicians, we had no data from well-controlled experimental studies to answer these questions. This study is the first to ask these questions experimentally.”

Previous studies have documented that both treatment types can result in significant child gains in language understanding and use, learning rates, and cognitive and adaptive skills. However, recommendations for a specific number of hours per week of treatment have been based on assumptions rather than high-quality experimental evidence.

The two interventions vary considerably in their delivery style and underlying theories. EIBI is based on applied behavior analysis and uses simple, structured instructions to teach the children. ESDM is naturalistic and based on developmental and behavioral sciences with an interactive style embedded in everyday activities, both play and typical routines.

Neither the type of the intervention, nor the intensity of delivery led to a significant difference in children’s rate of progress, the authors found. 

The trial was designed to provide objective answers about the effect of initial child characteristics, treatment styles and treatment intensities on the child’s progress over time, and progress was assessed by measuring  key developmental and symptom indicators.

To conduct the study, 87 toddlers with autism, aged between the ages of 12 and 30 months from three university sites were randomly assigned to one of four intervention groups – 15 or 25 hours of ESDM; 15 or 25 hours of EIBI, based on their age or developmental level. 

The researchers delivered one year of one-on-one interventions in homes and childcare settings. They also provided caregiver coaching to the families through two 1.5-hour sessions per month. According to Professor Rogers, the ESDM and EIBI treatments were delivered “at the highest quality.”

Each child received four clinic assessments from the time of enrollment, at six-month intervals. Therapists assessed progress daily and updated the intervention frequently to meet children’s changing developmental and behavioral needs.

The researchers found that neither style nor intensity of intervention had a differing effect overall on the study’s four outcome measures: children’s progress in receptive language, expressive communication, nonverbal ability and autism symptom change. They also found that the treatment providers in both models used the models flexibly to meet individual children’s needs. 

Both models tended to provide greater structure and practice for children who needed it, and more child choice and naturalistic teaching for children who were ready for it.

“Parents may find it reassuring that even within highly specified treatment approaches like these two, therapists still adjust to individual child needs,” researchers said.

The initial severity of developmental delay and autism symptom severity did not influence the impact of treatment style or intensity on any of the outcomes.

To read the study in full, please see here.