Study Protocol for a Cluster, Randomized, Controlled Community Effectiveness Trial of the Early Start Denver Model (ESDM) Compared to Community Early Behavioral Intervention (EBI) in Community Programs serving Young Autistic Children: Partnering for Autism: Learning more to improve Services (PALMS).
This upcoming 300-child cluster trial will finally show if ESDM outperforms everyday community ABA for preschoolers with autism.
01Research in Context
What this study did
Stahmer et al. (2024) wrote the plan for a big fair test. They will put 300 preschoolers with autism into either the Early Start Denver Model or the usual community ABA.
Programs, not kids, get picked by coin flip. This keeps real-world messiness like staff turnover and mixed groups.
What they found
Nothing yet. The trial is still running. The paper only tells us how they will check language, social, and daily-living skills after one and two years.
How this fits with other research
Van Gaasbeek et al. (2026) pooled 29 studies and saw large gains when early ABA is done in community clinics. Rodgers et al. (2021) found smaller, medium IQ gains after two years. The new trial will show which picture is closer to truth for ESDM.
Dudley et al. (2019) compared two Canadian public programs and saw equal adaptive gains even when hours differed. PALMS will test if ESDM beats those same kinds of mixed community packages.
Dzanko et al. (2026) got decent progress with only 3 hours per week in low-resource areas. PALMS will ask if more hours of a set model do even better.
Why it matters
You need solid numbers before you ask funders for ESDM training. When the trial ends you will know if switching your whole preschool team to ESDM really beats the mix of PRT, EIBI, and parent coaching you already do. If gains are equal, you can keep flexible community blends and save training dollars. If ESDM wins big, you have data to justify the cost and time of full model adoption.
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02At a glance
03Original abstract
The rising number of children identified with autism has led to exponential growth in for-profit applied behavior analysis (ABA) agencies and the use of highly structured approaches that may not be developmentally appropriate for young children. Multiple clinical trials support naturalistic developmental behavior interventions (NDBIs) that integrate ABA and developmental science and are considered best practices for young autistic children. The Early Start Denver Model (ESDM) is a comprehensive NDBI shown to improve social communication outcomes for young autistic children in several controlled efficacy studies. However, effectiveness data regarding NDBI use in community-based agencies are limited. This study uses a community-partnered approach to test the effectiveness of ESDM compared to usual early behavioral intervention (EBI) for improving social communication and language in autistic children served by community agencies. This is a hybrid type 1 cluster-randomized controlled trial with 2 conditions: ESDM and EBI. In the intervention group, supervising providers will receive training in ESDM; in the control group, they will continue EBI as usual. We will enroll and randomize 100 supervisors (50 ESDM, 50 EBI) by region. Each supervisor enrolls 3 families of autistic children under age 5 (n = 300) and accompanying behavior technicians (n = 200). The primary outcome is child language and social communication at 6 and 12 months. Secondary outcomes include child adaptive behavior, caregiver use of ESDM strategies, and provider intervention fidelity. Child social motivation and caregiver fidelity will be tested as mediating variables. ESDM implementation determinants will be explored using mixed methods. This study will contribute novel knowledge on ESDM effectiveness, the variables that mediate and moderate child outcomes, and engagement of its mechanisms in community use. We expect results from this trial to increase community availability of this model and access to high-quality intervention for young autistic children, especially those who depend on publicly funded intervention services. Understanding implementation determinants will aid scale-up of effective models within communities. Clinicaltrials.gov identifier number NCT06005285. Registered on August 21, 2023. Issue date 6 August 2024; Protocol amendment number: 02.
BMC Psychology, 2024 · doi:10.1186/s40359-024-02020-0