A Clinical Trial of a Commercially Available Intervention in Pediatric Patients with Autism Spectrum Disorder and Moderate Language Delays

Posted April 23, 2021

Lawrence Scahill, M.S.N., Ph.D., Emory University and Marcus Autism Center

Dr. Lawrence Scahill
Dr. Lawrence Scahill

According to recent data published by the Autism and Development Disabilities Monitoring (ADDM) network, the estimated prevalence of autism spectrum disorder (ASD) in children is 1.85%.1 Many children with ASD also have language delays ranging from mild to severe. Children with severe language delay require intervention by highly trained therapists in specialized settings.2 Although less severe, moderate language delay is common in children with ASD, adds to overall social impairment, and interferes with learning. Through a Fiscal Year 2014 Clinical Trial Award, Dr. Lawrence Scahill and colleagues at the Marcus Autism Center evaluated the efficacy of Direct Instruction – Language for Learning (DI) in children with ASD and moderate language delay. DI is a structured, commercially available language development program with research support for treating language delay in the general pediatric population. To date, DI has not been well studied in children with ASD and moderate language delay.

In this study, children with ASD and moderate language delay were randomly assigned to continue treatment as usual (TAU) only or to receive DI+TAU for 6 months. TAU included speech therapy in school, in the community, or both. Following the 6-month randomized phase, children receiving TAU only were offered the option of 6 months of treatment with DI. Eighty-three children (71 boys, 12 girls) aged 4 years to 7 years 11 months were randomly assigned to DI+TAU (n=42) or TAU only (n=41). The primary outcome was the standard score on the Clinical Evaluation of Language Fundamentals (CELF) as assessed by a speech pathologist. The key secondary measure was the proportion of children that scored as “Much Improved” or “Very Much Improved” on the Clinical Global Impression Improvement (CGI-I) scale as rated by a clinician. Findings revealed that, prior to treatment, the average CELF scores were 59.2 +10.2 and 55.7 +9.2 for DI and TAU respectively, indicative of a moderate language delay. Additionally, at the end of the intervention, DI+TAU showed a 4.8-point (8.1%) increase on the CELF scores versus a score of 2.3 points (4.1%) in the TAU group. When adjusted for baseline intelligence quotient scores, the difference between DI+TAU compared to TAU at Week 24 was statistically significant. Specifically, the clinician rated 54.8% of DI+TAU participants as “Much Improved” or “Very Much Improved” on the CGI-I scale compared to 22.0% in the TAU group.

These preliminary results indicate that DI in combination with TAU was beneficial for over half of children with ASD and moderate language delay compared to about a third of children in the TAU-only group. Children with intelligent quotient scores below 70 and those with lower language skills did not show any clear benefit in receiving the DI + TAU option. The development and availability of the DI program, specifically when paired with TAU, appears to provide an additional benefit to children with ASD. Importantly, a distinct advantage of DI is that it can be administered by a variety of educators, clinicians, and other healthcare professionals in a variety of settings and may be specifically helpful in providing care to underserved communities.




Public and Technical Abstracts: Efficacy of the Direct Instruction Language for Learning Program to Promote Expressive and Receptive Language in Children with Autism Spectrum Disorder

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Last updated Thursday, May 26, 2022