Kathleen M. Holehan, MA, BCBA, LBA
Thomas Zane, PhD, BCBA-D
Department of Applied Behavioral Science, University of Kansas
In recent years, the prevalence of autism spectrum disorder (ASD) has increased substantially. In the early 2000s, ASD was estimated to occur in approximately 1 in 150 children; as of 2018, this number has increased to approximately 1 in 59 children (Centers for Disease Control and Prevention, 2018). Research has shown early identification of ASD has resulted in an increased number of infants and toddlers seeking treatment from early intervention programs (Stahmer & Mandell, 2007). Access to early and appropriate intervention has the potential to impact and improve the child’s life long outcomes (Ryberg, 2015; Schreibman, et al., 2015). As families and professionals push for early diagnoses and treatment, ASD diagnoses may continue to rise. Clinicians must support these needs with evidence-based treatments designed specifically for early learners (Vismara, Colombi, & Rogers, 2009). One model that is growing in popularity is the Early Start Denver Model (ESDM), an early intensive intervention designed specifically for children ages 18-48 months diagnosed with ASD.
What is the conceptual link between ASD and ESDM?
ESDM was developed in the 1980s by two psychologists, Sally Rogers and Geraldine Dawson. The ESDM combines techniques employed in the Denver Model (e.g., Rogers, et al., 2006) and Pivotal Response Training (PRT; Koegel & Koegel, 2006). The Denver Model was developed for preschoolers with ASD while PRT was designed to target four pivotal areas including: motivation to learn, responding to cues, self-management, and self-initiation (Rogers & Dawson, 2010).
The goals of ESDM are to facilitate positive and playful interactions between the child and therapist (e.g., parent, professional, teacher) with a heavy focus on the development of social learning, social-cognitive development, and social communication (Baril & Humphreys, 2017; Rogers & Dawson, 2010; Rogers, Dawson, & Vismara, 2012). Before beginning ESDM treatment,the authors recommend that the ESDM Curriculum Checklist (Rogers & Dawson, 2010) be used as a baseline measure. The checklist involves a combination of observation and parent report and is used to evaluate the child’s skill level across several developmental domains such as language, social skills, imitation, cognition, play, and motor and self-help skills. Using the information gathered in the baseline assessment, learning objectives or target goals are developed and implemented on an individual basis. Target goals are then embedded within the child’s natural environment capitalizing on the child’s spontaneous interests and motivations (Vivanti et al., 2014). Progress toward target goals is evaluated every 12 weeks using the ESDM Curriculum Checklist. The idea is that by participating in experiences that require positive social interactions, the more aware the child will become to their social environment leading to increased social interactions (Vivanti, Dissanayake, Zierhut, Rogers, & Victorian ASELCC Team, 2013).
Is there any research to support ESDM?
Currently, there is a breadth of research available on the use of ESDM to treat ASD. Although there is a large amount of research supporting the use of ESDM as an effective evidence-based treatment, the findings lack empirical validity (i.e., the experimental rigor of the available research is weak). In general, ESDM studies focus on training parents and professionals to implement ESDM interventions and evaluate the fidelity of the training on the interventions (e.g., Vismara, et al., 2009; Vismara & Rogers, 2008; Rogers et al., 2012; Vismara, McCormick, Young, Nadhan, & Monlux, 2013) and implementing and evaluating ESDM in community and group-based settings (e.g., Eapen, Crncec, & Walter, 2013; Vivanti et al., 2014).
Vismara and Rogers (2008) implemented and evaluated the ESDM with a child who presented a behavioral profile similar to ASD at nine months of age. Behavioral Skills Training (BST) was used to train parents on the implementation of interventions facilitating social engagement, imitation, emotional sharing, and communication skills. The intervention consisted of parents implementing ESDM for 1.5 hours a week over a 12-week period. Researchers conducted four follow-up assessments across three months after intervention sessions. Results of the study indicated parents can be trained to implement ESDM with fidelity. Results also indicated after receiving ESDM intervention, the child emitted higher rates of spontaneous functional verbal utterances and imitative behaviors. Behaviors maintained and were generalized during follow-ups. Although the study did show improvements in the child’s behavior, there were several methodological limitations. First, the infant was outside the recommended age range to receive ESDM treatment. That is, the child was nine months old, ESDM treatment is recommended for children 18-48 months old. It is unknown what effect the age difference had on treatment outcomes. Second, the study employed a single-case design with a short baseline. In other words, it is not possible to discern that gains made were due to intervention rather than skills acquired naturally over time. Thus, even with the developmental gains made, experimental control was not demonstrated. Due to lack of experimental control, researchers and readers cannot be sure that ESDM alone was responsible for behavior change. Finally, during the follow-up assessments the infant began receiving additional intervention programs which may have influenced responding independent of the ESDM intervention. This represents another significant threat to internal validity.
To address the methodological limitations of Vismara and Rogers (2008) and other ESDM studies evaluating the fidelity of training on the intervention, Rogers et al. (2012) conducted a randomized control trial to analyze the efficacy of parent delivery ESDM (P-ESDM). In total, 98 children ranging from 12-24 months were randomly assigned to either the treatment (i.e., P-ESDM) or control (i.e., community treatment as usual) group. BST was used to train parents on the implementation of ESDM (e.g., joint attention, imitation, speech development). ESDM treatment sessions consisted of 12 consecutive, hour-long sessions over a three-month period. Results indicated higher parent ESDM fidelity scores were related to those children who at the start of the study exhibited higher developmental scores. Results further indicated there was no difference in developmental outcomes with either group. That is, neither the test nor control group’s showed significant improvements. Although there were no significant improvements in either group, the study had one major limitation. That is, researchers did not control for either groups exposure to additional treatments which may have occurred. The authors indicated children in both groups may have received additional treatments. Additionally, it was possible children in the control group were exposed to more treatment hours than those in the ESDM group.
With limitations, studies have shown the ESDM is effective when implemented in an individual (i.e., 1:1) context (e.g., Vismara & Rogers, 2008; Dawson, et al., 2010). Professionals have argued the feasibility of ESDM in community and group-based settings (e.g., preschool classroom). Eapen, Crncec, and Walter (2013) examined and evaluated the efficacy of the ESDM intervention in a community group setting. Children received two half-hour individual sessions per week and 15-20 hours of ESDM intervention in a group with other children diagnosed with ASD. Results indicated a significant increase in children’s mean overall development quotient (DQ) from pre-to-post-intervention with the highest increases in the areas of receptive language and communication. Although Eapen et al. (2013) demonstrated ESDM can be implemented and produce effective results in community group settings, the methodology lacked experimental control. Results indicated higher parent ESDM fidelity scores were related to those children who exhibited higher developmental scores at the start of the study.
To address the methodological limitations, Vivanti et al. (2014) evaluated the effectiveness and feasibility of ESDM treatments in a community-care setting. Specifically, researchers used a randomized control trial to evaluate ESDM implemented with 27 preschoolers for 15-25 hours a week. Researchers compared these data to 30 preschool children who received a community-based educational program. Researchers controlled for similar settings and intensity across groups. Results indicated children in the ESDM group made significantly larger improvements (in rate of development and receptive language abilities) than those in the control group. As with other studies evaluating ESDM, researchers did not control for additional treatments children may have been receiving in conjunction with ESDM and while participating in the control group.
Cidav et al. (2017) used the data from a previously conducted randomized trial to determine the effect of ESDM on the costs of health care services. Researchers compared the annual service use and costs during treatment of 21 children receiving ESDM treatment to 18 children receiving community care treatment. All 39 children’s parents were interviewed about the specific services their child received (e.g., occupational therapy (OT), speech therapy, physical therapy (PT), ESDM) every six months from the start of ESDM to the final follow-up at six years of age. Services reported by parents were grouped into the following eight categories: ESDM, ABA/Early Intensive Behavioral Intervention, general education, OT/PT, social skills training, special education, speech therapy, and other miscellaneous interventions (e.g., biomedical therapy, music therapy, and nutritional therapy). These services were then costed by category by applying unit hourly costs. Results indicated during intervention service hours and costs between the ESDM and community care groups were about the same across all categories. However, post-intervention service hours were less for the ESDM group than for the community service group, but the difference was not statistically significant. Additionally, total post-intervention costs were significantly lower for the ESDM group than the community service group. Although results indicated a significantly lower cost for additional treatment following the use of the ESDM, this study had methodological limitations. First, as with other studies evaluating ESDM, researchers did not control for other treatments children were receiving in conjunction with ESDM. Although additional treatments were factored in to the total cost (i.e., placed in a category and unit hourly costs applied), the cost of ESDM in isolation was not compared to the costs of community services. That is, it may be possible that ESDM in isolation does not reduce the future costs of services. In addition to the methodological concerns, the study has not been replicated by other researchers.
Future Research
The current research on ESDM is lacking in experimental control, empirical validity, and objective measurement of treatment effects. First, the extent to which child improvements can be directly linked to the ESDM treatment alone is not known. Second, a majority of the studies have allowed children either in the test or control group to receive additional community treatment while participating in the current study confounding results. Lastly, a majority of the studies conducted have included at least one of the original developers of the ESDM which raises questions about biases and the ESDMs ability to be replicated.
Future research should continue to evaluate the efficacy of ESDM as a treatment for children with ASD in several ways. First, more studies involving randomized control groups need to be conducted to ensure behavior is changing when and only when ESDM is implemented. Second, more comparative studies are needed in order to assess the extent to which ESDM is more effective than other ASD treatments for young children (e.g., applied behavior analysis). Third, additional replications implemented by independent researchers are necessary to further validate ESDM as an effective treatment for young children. Lastly, additional research comparing the costs of ESDM to other treatments is needed.
What is the bottom line?
Although ESDM shows promise as an effective intervention and seems like an attractive treatment, current studies have not demonstrated experimental control, empirical validity, or objective measurement of treatment effects. Initial studies proposing and evaluating ESDM demonstrated weak research designs (e.g., lacked control group, small number of participants, issues with feasibility). More recent studies have begun implementing and evaluating the effectiveness of ESDM in randomized controlled trials with mixed results. Although researchers have attempted to address one methodological limitation, there has yet to be a study showing the effects of ESDM free of confounds (e.g., free of other treatments being administered) or biases (e.g., replicated with independent researchers, parents, and therapists). Acceptance of the ESDM as an evidenced-based practice must wait for further replications.
References
Baril, E. M., & Humphreys, B. P. (2017). An evaluation of the research evidence on the Early Start Denver Model. Journal of Early Intervention, 39(4), 321-338. doi:10.1177/1053815117722618
Centers for Disease Control and Prevention. (2018). Prevalence of autism spectrum disorder among children aged 8 years — autism and developmental disabilities monitoring network, 11 sites, United States, 2014. MMWR Surveillance Summaries, 67(6), 1-23. doi: http://dx.doi.org/10.15585/mmwr.ss6706a1
Cidav, Z., Munson, J., Estes, A., Dawson, G., Rogers, S., & Mandell, D. (2017). Cost offset associated with Early Start Denver Model for children with autism. Journal of the American Academy of Child and Adolescent Psychiatry, 56(9), 777-783.
Dawson, G., Rogers, S., Munson, J., Smith, M., Winter, J., Greenson, J., Donaldson, A., & Varley, J. (2009). Randomized controlled trial of an intervention for toddlers with autism: The Early Start Denver Model. Pediatrics, 125(1), 17-23.
Eapen, V., Crncec, R., & Walter, A. (2013). Clinical outcomes of an early intervention program for preschool children with autism spectrum disorder in a community group setting. BMC Pediatrics, 13(1), Article 3. doi:10.1186/1471-2431-13-3
Koegel, R. L., & Koegel, L. K. (2006). Pivotal response treatments for autism: Communication, social, & academic development. Baltimore, MD, US: Paul H Brookes Publishing.
Rogers, S. J., & Dawson, G. (2010). Early Start Denver Model for young children with autism: Promoting language, learning, and engagement. New York, NY: The Guilford Press.
Rogers, S. J., Dawson, G., & Vismara, L. A., (2012). An early start for your child with autism. New York, NY: The Guilford Press.
Rogers, S. J., Estes, A., Lord, C., Vismara, L., Winter, J., Fitzpatrick, A., . . . Dawson, G. (2012). Effects of a brief Early Start Denver Model (ESDM)-based parent intervention on toddlers at risk for autism spectrum disorders: A randomized control trial. Journal of the American Academy of Child & Adolescent Psychiatry, 51, 1052-1065. doi:10.1016/j.jaac/2012.08.003
Rogers, S. J., Hayden, D., Charlifue-Smith, R., Hall, T., & Hayes, A. (2006). Teaching young nonverbal children with autism useful speech: A pilot study of the Denver model and PROMPT interventions. Journal of Autism and Developmental Disorders, 36(8), 1007-1024. Retrieved from https://escholarship.org/uc/item/3xf7w6b8
Ryberg, K. H. (2015). Evidence for the implementation of the Early Start Denver Model for young children with autism spectrum disorder. Journal of the American Psychiatric Nurses Association, 21(5), 327-337. doi:10.1177/1078390315608165
Schreibman, L., Dawson, G., Stahmer, A. C., Landa, R., Rogers, S. J., McGee, G. G., … Halliday, A. (2015). Naturalistic developmental behavioral interventions: Empirically validated treatments for autism spectrum disorder. Journal of Autism and Developmental Disorders, 45(8): 2411–2428. DOI 10.1007/s10803-015-2407-8
Stahmer, A. C., & Mandell, D. S. (2007). State infant/toddler program policies for eligibility and services provision for young children with autism. Administration and Policy in Mental Health, 34(1), 29-37.
Vismara, L. A., Colombi, C., Rogers, S. J. (2009). Can one hour per week of therapy lead to lasting changes in young children with autism? Autism, 13(1), 93-115. doi:10.1177/1362361307098516
Vismara, L. A., McCormick, C., Young, G. S., Nadhan, A., & Monlux, K. (2013). Preliminary findings of a telehealth approach to parent training in autism. Journal of Autism and Developmental Disorders, 43, 2953-2969. doi:10.1007/s10803-013-1841-8
Vismara, L. A., & Rogers, S. J. (2008). The Early Start Denver model: A case study of an innovative practice. Journal of Early Intervention, 31, 91-108. doi:10.1177/1053815108325578
Vivanti, G., Dissanayake, C., Zierhut, C., Rogers, S. J., & Victorian ASELCC Team. (2013). Brief report: Predictors of outcomes in the Early Start Denver Model delivered in a group setting. Journal of Autism and Developmental Disorders, 43, 1717-1724. doi:10.1007/s10803-012-1705-7
Vivanti, G., Paynter, J., Duncan, E., Fothergill, H., Dissanayake, C., Rogers, S., & Victorian ASELCC Team. (2014). Effectiveness and feasibility of the Early Start Denver Model implemented in a group-based community child care setting. Journal of Autism and Developmental Disorders, 44, 3140-3153. doi:10.1007/s10803-014-2168-9
Citation for this article:
Holehan, K. M., & Zane, T. (2019). Is there science behind that?: The Early Start Denver Model. Science in Autism Treatment, 16(2).
