The Search for Evidence-Based Practices for Individuals with ASD Continues
This post is by guest blogger, Samuel L. Odom, Ph.D. Dr. Odom is the director of the Frank Porter Graham Child Development Institute and professor in the School of Education at the University of North Carolina. He is the author or co-author of many refereed journal articles and editor or co-editor of seven books on early childhood intervention and developmental disabilities.
Many efforts exist now to locate practices, intervention approaches, and treatments that improve the development, functioning, and well-being of individuals with Autism Spectrum Disorders (ASD) and their families. Inspired by the model established by the Cochrane Collaboration (http://www.cochrane.org/ ) in evidence-based medicine, investigators from a variety of organizations (i.e., the National Autism Center, National Professional Development Center on ASD, What Works Clearinghouse) have conducted and are continuing to conduct systematic reviews and evaluations of the research literature to discern approaches with sufficient scientific evidence of efficacy to support their use. Such reviews have practical importance because they guide practitioners, physicians, and family members in their selection of practices to use with individuals with autism. They also have social policy implications in that they may guide the selection of services that received funding from social service agencies.
A research group at the Vanderbilt Evidence Based Practice Center has just published three such reviews in Pediatrics that contribute substantially to the growing literature on evidence-based practice. Following a standard and rigorous evaluation process, this research group reviewed the literature from 2000 to 2010 and reported their findings for Early Intensive Intervention (Warren et al., 2011), Medical Treatments for challenging and repetitive behavior (McPeeters et al., 2011), and one additional specific medical treatment, Secretin, thought to have generalized effects (Krishnaswami, McPheeters, &Veenstra-VanderWeele, 2011)
Early intensive interventions for children with ASD are behavioral or developmental in nature. Such interventions focus on improving the intellectual, communication, social, and adaptive functioning of young children with autism. In their review, Warren et al. (2011) examined the evidence for three comprehensive treatment approaches as well as a set of other approaches for which less research had been reported. The Lovaas/UCLA model has the largest set of research literature, with one study being judged of good quality, and a set of other studies being of lesser quality but documenting strong effects for the model. The Lovaas/UCLA approach is an intensive, individualized behavior therapy model that emphasizes application of applied behavior analysis principles and discrete trial training. The Early Start/Denver model also had one randomized study and a second supportive study documenting efficacy. The Early Start/Denver Model also employs applied behavior analysis principles within a functional developmental conceptual framework. The third set of intervention practices focused on training parents to deliver primarily applied behavior analysis interventions in the home and community to promote communication skills, IQ, and adaptive behavior. Three studies of fair quality substantiated this intervention approach. Warren and colleagues concluded that the early intensive interventions, as a group, have promising outcomes but the evidence of efficacy is at this point modest. They noted that such interventions have “significant potential” but require further research to establish efficacy more strongly. To quote the authors of the review, “At present, a paucity of research leaves us with individual studies that suggest promising outcomes but a critical need for replication, extension, and controlled studies of the factors that moderate treatment outcome. Thus, the low and insufficient strength of evidence reported in this review should not be interpreted as evidence that the interventions are not effective but, rather, as encouragement for additional research.”
In their examination of medical treatment, McPheeters et al. (2011) note that prescribing medication for co-morbid symptoms associated with ASD (e.g., challenging behavior, stereotypic behavior) is a common practice but reviews of evidence for outcomes have been limited. They examined the literatures for antipsychotic, Selective Serotonin Re-Uptake Inhibitors (SSRIs), and stimulant medications.
Two antipsychotic medications studied most often, risperidone and aripiprazole, targeted challenging behaviors and repetitive behaviors. Randomized studies of sufficient but varying quality documented the positive effect of both medications on ratings of targeted behavioral outcomes for children with ASD, but these studies also consistently documented adverse side effects such as weight gain. McPheeters et al. proposed that the reports of such consistent side effects might limit the use of such medications for all but those “individuals with significant impairments or risk of injury.”
Less or weaker evidence were found for the latter two forms of medication. One acceptable randomized study did document the effects of the SSRI Fluoxetine on repetitive behavior and a second randomized study of fair quality documented the effect of SSRI citalopram on challenging behavior. McPheeters et al. concluded, however, that the overall evidence for the use of SSRIs was insufficient. Similarly, although the RUPP Autism Network study of the effects of methylphenidate (a stimulant) on challenging behavior did reveal some positive effects, albeit with side effects, McPheeters et al concluded that the evidence for stimulants was insufficient. As a general conclusion, the authors proposed that literature addressing the use of medications for children with ASD lacks sufficient quality, studies has often been funded by pharmaceutical companies (without independent replication), and medications have not been compared with, or assessed in combination with, behavioral interventions that have the same targeted outcomes.
In a third review, Krishnaswami et al., (2010) examined the research on the use of Secretin for the treatment of communication impairments, symptom severity, and social deficits for children with ASD. Secretin, a medication used to treat gastrointestinal disorders and pancreatic functions, is also theorized to affect the central nervous system and act as a neurotransmitter. Its proposed use for treatment of ASD was based on an uncontrolled case series of three children. The Krishnaswami et al. literature review identified eight studies meeting their inclusion criteria, with quality of the studies ranging from good to fair. Across studies, no positive effects for use of Secretin were found. This was the most unambiguous finding of the three reviews by this group.
The three reviews conducted and reported by the Vanderbilt Evidence-Based Practice Center contribute to the ongoing knowledge about the “state of the art” in interventions and treatment for children with ASD. Their rigorous and conservative evaluations highlight the practices that are beginning to come forward as efficacious for individuals with ASD (e.g., some early intervention models, antipsychotic medications), the implications of employing some efficacious treatments (e.g., severe side effects), and treatments applied in the past that now have strong evidence of non-effects (i.e., Secretin). Importantly, these reviews speak strongly to the importance of future, high quality research in both the behavioral and medical treatment areas.
Zachary Warren, Melissa L. McPheeters, Nila Sathe, Jennifer H. Foss-Feig, Allison Glasser, and Jeremy Veenstra-VanderWeele. Pediatrics published online April 4, 2011 (10.1542/peds.2011-0426).
Melissa L. McPheeters, Zachary Warren, Nila Sathe, Jennifer L. Bruzek, Shanthi Krishnaswami, Rebecca N. Jerome, and Jeremy Veenstra-VanderWeele. Pediatrics published online April 4, 2011 (10.1542/peds.2011-0427).
Shanthi Krishnaswami, Melissa L. McPheeters, and Jeremy Veenstra-VanderWeele. Pediatrics published online April 4, 2011 (10.1542/peds.2011-0428)