Numerous single studies indicate that ABA methods are effective in improv-ing communication (Goldstein 2002), social skills (McConnell 2002), and
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management of problem behavior (Horner et al. 2002). Research also has been conducted on the effects of combining ABA methods into an intervention pro-gram or model. Table 8–1 summarizes some of the main models for delivering ABA interventions to individuals with ASDs. Some models are comprehensive, designed to address all areas of need, whereas others are directed toward a more circumscribed, specific set of goals.
Early Intensive Behavioral Intervention
One comprehensive approach is early intensive behavioral intervention (EIBI).
EIBI is characterized by 20–40 hours per week of treatment for 2 or more years, beginning before age 5 years. EIBI involves carefully structured, one-on-one, and small-group interventions based on a broad curriculum that em-phasizes communication, social skills, cognition, and pre-academic skills (e.g., imitation, matching, letter and number concepts) (Leaf and McEachin 1999).
Once children reach school age, they may continue participation in behavior-ally based educational approaches and/or more traditional special or regular education techniques to address areas of ongoing need, as described later in the subsection “Other Applied Behavior Analysis Models.”
In a seminal study that used matched control groups and multiple pre-treatment and follow-up measures, Lovaas (1987) reported an average gain of 20 IQ points for 19 children with autism participating in 40 hours per week of EIBI for 2 years or more. The treatment initially took place in children’s homes, with a focus on highly structured one-on-one instruction. As children progressed, treatment focused on promoting social interaction and entering children into community settings such as schools. Nine children from the EIBI group (47%) achieved average intellectual functioning and were subsequently enrolled in general education classrooms. In contrast, IQ scores of children in two control groups (i.e., a group receiving only 10 hours of behavioral inter-vention and a group receiving other types of interinter-vention) remained virtually unchanged, with only 1 child out of 40 demonstrating intellectual functioning in the normal range. A follow-up study (McEachin et al. 1993) determined that the intellectual and academic gains of the original EIBI group remained stable several years after treatment up to, on average, 13 years of age. Subsequent stud-ies have yielded smaller gains than those reported by Lovaas (1987) but con-firm that EIBI may increase scores on standardized tests of intelligence, lan-guage, and adaptive behavior (Smith 1999). Although these studies, including
Applied Behavior Analysis in the Treatment of Autism157 Table 8–1. Some models of applied behavior analysis (ABA) service delivery
Type of service Example Description
Comprehensive intervention Early intensive behavioral
intervention
UCLA Young Autism Project (Lovaas 1987)
40 hours per week of individual, in-home intervention based on a comprehensive curriculum for children with autism spectrum disorders (ASDs) who begin treatment before age 4 years ABA classrooms Princeton Child Development
Institute (McClannahan and Krantz 1997)
25 hours per week in a self-contained classroom with ABA interventions administered individually or in small groups for school-age children with autism
Occupational and residential supports
Eden Model (Holmes 1997) Residential facility with ABA intervention for self-help and vocational skills
Supported inclusion LEAP Preschool (Strain and Cordisco 1994)
15 hours per week of intervention, emphasizing peer-mediated social skills training in a preschool classroom containing both children with ASDs and typically developing children Skills-focused models
Individual treatment Communication: Picture Exchange Communication System (Bondy and Frost 2001)
Two service providers working together to teach an individual with an ASD to select pictures and give them to a communication partner to indicate wants or needs
Self-management:
Contingency contracting (Mruzek et al. 2007)
Written contract developed collaboratively with high-functioning children with ASDs to reduce problem behavior
Academics: Direct Instruction reading (Engelmann et al. 1988)
Structured ABA curriculum for teaching reading skills individually or in groups
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Skills-focused models (continued)
Parent training Parent-delivered pivotal response training (Schreibman and Koegel 2005)
Instruction to parents on creating opportunities to teach their children with ASDs in the context of everyday activities
Staff/teacher training Behavioral skills training for teachers (Sarokoff and Sturmey 2004)
Didactic instruction and in vivo supervision for teachers on the use of structured teaching procedures
Peer tutoring Peer-mediated social skills training (Odom et al. 1999)
Teaching peers to serve as tutors to help individuals with ASDs increase their social interactions
Note. LEAP=Learning Experiences: An Alternative Program for Preschoolers and Parents.
Table 8–1. Some models of applied behavior analysis (ABA) service delivery (continued)
Type of service Example Description
Applied Behavior Analysis in the Treatment of Autism 159
the 1987 Lovaas report, have methodological weaknesses, most notably nonran-dom assignment of participants to treatment groups, the body of scientific evi-dence indicates EIBI may be very effective as an intervention for autism.
In addition to the EIBI model developed by Lovaas and colleagues, there are a number of other EIBI models (Handleman and Harris 2001). Some, such as Learning Experiences: An Alternative Program for Preschoolers and Parents (LEAP;
Strain and Cordisco 1994), take place at school rather than home. LEAP includes preschool services in which children with ASDs are integrated with typically de-veloping peers and the parents of the children with ASDs are given extensive training. Interventions strongly emphasize promoting social skills using ABA teaching methods. An uncontrolled follow-up study indicated that six children who entered LEAP between the ages of 30 and 53 months maintained their behavioral and developmental gains at age 10 years (Strain and Hoyson 2000).
Another model is pivotal response treatment (PRT), which aims to teach pivotal responses that, when acquired, improve performance across numerous skill areas (Koegel and Koegel 2006). A number of studies have documented short-term ef-fects of PRT, but data on long-term outcomes are currently unavailable. PRT may be provided to preschool-age children or to older children with ASDs.
Some findings suggest that ABA-based early intervention may be more ef-fective than alternative approaches. Notably, Howard et al. (2005), compared 14 months of EIBI to two other interventions: 1) intensive, “eclectic” autism treatment (30 hours per week of one-on-one and one-on-two instruction) that includes TEACCH (Treatment and Education of Autistic and Related Com-munication-Handicapped Children) methodology (Schopler 1997), sensory integrative therapy (Bundy et al. 2002), and some ABA; and 2) nonintensive public special education. Participants were carefully matched (but not ran-domly assigned) to groups. Although the groups did not differ significantly on any pretreatment measure, the EIBI group demonstrated an average increase of 31 points in IQ (59 at intake and 90 at follow-up), whereas participants in the other two treatments showed an average increase of only 9 points. The EIBI group also made greater gains in scores on language and adaptive behavior measures. Thus, intensity of treatment in the absence of consistently applied ABA strategies and techniques was not sufficient for treatment effectiveness in this study.
Because of the intensity of EIBI, concerns have been raised about the feasi-bility of implementing it in community settings. Although one study of
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munity-based treatment yielded disappointing results (Bibby et al. 2002), oth-ers suggest that it may be effective if close supervision is provided. For example, Sallows and Graupner (2005) found that treatment run by parents who received approximately 6 hours of expert consultation per month for 4 years yielded outcomes similar to those of clinic-directed treatment.
Other Applied Behavior Analysis Models
Although EIBI was developed for toddlers and preschoolers with autism, and thus is appropriate for that age group, there are also comprehensive ABA mod-els for older children and adults with ASDs throughout the lifespan. These programs take place in specialized classrooms, residences, or occupational set-tings. They differ from EIBI in that they place less emphasis on intensive, in-dividualized, structured teaching and focus more on facilitating participation in group activities and fostering the ability to complete tasks independently (without direct supervision). Research shows that persons with ASDs in these programs learn many new skills (McClannahan et al. 2002). Still, little informa-tion is available on long-term outcomes such as whether graduates of the pro-grams succeed afterward in less specialized settings.
Specific skills models may involve working directly with persons with ASDs in a particular area (e.g., social interaction) or training parents, peers, or ser-vice providers to implement ABA interventions. Training may take place at the home, in an inclusive education program or community setting, or at a spe-cialized school or job site. It typically includes instruction on characteristics of ASDs, assistance with identifying skills to teach, guided practice in applying ABA methods, direction on how to collect data on the effects of intervention, and establishment of a system for communication and collaboration between the intervention setting and home. The amount of training varies depending on the needs of the trainees and the individual with autism but often consists of a training workshop that lasts several days, followed by 1–2 hours per week of ongoing consultation. This consultation is gradually reduced as the trainees become proficient in applying ABA methods appropriate for the individual with ASD. Many studies document that with training, parents, peers, and edu-cators can become proficient at implementing ABA interventions under su-pervision of a professional ABA practitioner (Sarokoff and Sturmey 2004).
Again, however, little information is available on long-term outcomes.
Applied Behavior Analysis in the Treatment of Autism 161