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Article Excerpt
Educationally based programs are often the only form of intervention given to children with autism spectrum disorder (ASD) and are often the only form of support that their families receive (e.g., see Howlin & Moore, 1997; Osborne & Reed, in press, for surveys). Often these interventions are offered early in the child's development, and there is a perception that interventions offered early are more effective than those offered later (Lovaas, 1987). However, despite the ubiquity and perceived importance of educational approaches to the management of ASD, there are relatively few quantitative investigations of the comparative efficacy of such programs.
A number of early-teaching interventions have been suggested as offering benefit to some children with ASD. Applied behavior analysis (ABA) approaches have been widely investigated (e.g., Eikeseth, Smith, Jahr, & Eldevik, 2002; Howard, Sparkman, Cohen, Green, & Stanislaw, 2005; Lovaas, 1987; Smith, Annette, & Wynn, 2000). In addition, special nursery placements (see Charman, Howlin, Berry, & Prince, 2004; Gabriels, Hill, Pierce, Rogers, & Wehner, 2001), floortime (Greenspan & Wieder, 1997), and portage (e.g., Smith, 2000) have been offered as approaches to managing the problems associated with ASD. Some of these latter approaches have the benefit of being reasonably cost effective, but they suffer from the problem of having a scant evidence base with respect to their effectiveness in promoting the child's intellectual, educational, and social functioning.
The effectiveness of placement in specialist nursery provision has been studied, often as control conditions in the assessment of ABA programs. Such programs are often referred to in this literature as "generic" (e.g., Lovaas, 1987) and/or "eclectic" (e.g., Howard et al., 2005) programs. This is typically because such approaches do not follow a particular "brand name" approach to education, and they offer a variety of teaching methods (e.g., picture exchange systems, activities drawn from the TEACCH [Treatment and Education of Autistic and Related Communication Handicapped Children] model, circle time, social stories) that do not necessarily adhere to a single underlying philosophy, as do ABA approaches. The results from these studies of special nursery placements have not been particularly encouraging. Three studies have shown small improvements in intellectual functioning following special educational placement. Sheinkopf and Siegel (1998) found a 2-point increase in IQ across a year in children in special school provision, and Eikeseth et al. (2002) found a 4-point improvement in IQ over a year (using one-to-one techniques such as TEACCH and sensory-integration therapy). However, there was no improvement in adaptive behavior (as measured by the Vineland Adaptive Behaviour Scale). Gabriels et al. (2001), in a retrospective, 3-year study of children with ASD undergoing an eclectic approach to intervention, found a 5-point increase in IQ over 3 years.
In contrast, four studies have found no improvement in functioning. Shallows and Graupner (1999) found a 7-point decrease in IQ over a year. The remaining three studies in this latter group found no overall change in the standardized score of children in special educational placements with an eclectic approach to intervention. Howard et al. (2005) compared two groups of children with ASD undergoing either an intensive program in an autism special school or a less intensive program in a local community special education classroom. In neither case was there any change in a variety of assessments of intellectual functioning. Lovaas (1987) found no improvement for children undergoing generic educational interventions over a 3-year period. Charman et al. (2004) found no improvement in adaptive behavior scores as measured by the Vineland Adaptive Behaviour Scale (see also Eikeseth et al., 2002).
Unfortunately, the usefulness of many of these studies in assessing the impact of special educational provision on children with ASD is limited by the fact that many of these groups are derived from archive records (e.g., Gabriels et al., 2001; Sheinkopf & Siegel, 1998), rather than being studied contemporaneously with the other children in the study. Additionally, many of these studies employ different measurements both across participants and at baseline and follow up (e.g., Howard et al., 2005; Lovaas, 1987), thus, reducing the reliability of the data (see Magiati & Howlin, 2001). There are few studies of special educational placement that are prospective in nature and that use the same tests at baseline and follow up, which was the first aim of the current study.
Portage is an approach offered by numerous local education authorities in the United Kingdom for children with ASD. Portage is a home-based, parent-administered early intervention for developmental disabilities. Smith (2000) provides some data to suggest that portage programs can have an impact on social development of children with autism, and Reed, Osborne, and Gibson (2000) discuss some possible developments and limitations of this approach. However, this approach, although commonly used in practice, suffers from a great paucity of empirical evidence regarding its effectiveness.
Much current debate in educational literature has centered on ABA techniques as an intervention for ASD problems (see Connor, 1998; Mudford, Martin, Eikeseth, & Bibby, 2001). There are a number of different ABA approaches that have been outlined in a variety of sources (e.g., Greer, 1997; Koegel & Koegel, 2006; Lovaas, 1981; Lovaas & Smith, 1989; Sundberg & Michael, 2001; Twyman, 1998). In general, these approaches share a number of common features: (a) the one-to-one teaching of children with autism by adult tutors; (b) a discrete-trial reinforcement-based method; and (c) an intensive regime (up to 40 hr a week, for 3 years, in some instances). The initial results reported by Lovaas (1987) concerning the effectiveness of such an approach were remarkable. The children undergoing this approach made gains of up to 30 IQ points (a finding noted in some children with ASD undergoing special educational programs, see Gabriels et al., 2001), and just less than half of these children appeared to recover, that is, they were not noticeably different from normally developing children after 3 years of the intervention (a finding yet to be replicated).
There have been a number of critiques of this original piece of research (i.e., Lovaas, 1987) that have focused on problems both with the internal and external validity of the study (e.g., Connor, 1998; Gresham & MacMillan, 1997; Mudford et al., 2001). In terms of the internal validity of the Lovass (1987) study, it should be noted that different IQ tests were used at baseline and at follow up to assess the children's intellectual functioning, thus reducing the reliability of the measurement (Magiati & Howlin, 2001). This is not a unique problem with ABA studies (see earlier text). In terms of the threats to the external validity of the Lovaas (1987) study, the reliance on IQ as a sole measure may be questioned, given that IQ is not necessarily the main problem in autism functioning. Second, the sample chosen for the study reported by Lovaas (1987)were verbal, relatively high-functioning participants, who may have performed equally well with any intervention of a reasonable input (such as some of those noted earlier). Finally, the study reported by Lovaas (1987) was a clinic-based study and may not generalize to interventions as they are typically used in the parents' home, severely compromising the usefulness of the study. This issue has been highlighted in a number of recent reports of home-based ABA programs, which have questioned the extent to which the results of clinic-based assessments can be generalized to the type of ABA program that occurs in the community (Mudford et al.).
Although several of these critiques have been addressed in subsequent research, few, if any, studies have addressed them in a single investigation. For example, Eikeseth et al. (2002), and Howard et al. (2005), have used community-based rather than clinic-based samples, but neither used the same tests at baseline and at follow up. In light of this, a second aim of the current study was to assess the effectiveness of ABA approaches on a more typical sample of children with ASD, using the same instruments at baseline and follow up.
Thus, there are a number of issues that are clearly unresolved concerning the effectiveness of educational interventions for ASD. It appears critical to be able to assess the effectiveness of the ABA approach in community-based, rather than clinic-based, settings with participants more typically representative of those who present to local service providers (i.e., more severe symptoms, less linguistically able). It also appears important to utilize a wide range of instruments in the assessment procedure, not only to examine intellectual functioning, but also educational functioning, and adaptive behavior. Simultaneously providing evidence on the effectiveness of other interventions than ABA would not only allow these interventions to be assessed, but also would allow a well-matched alternate-treatment control group for the ABA studies, a comparison so far missing (Hohmann & Shear, 2002).
Given the previous considerations, the current study directly compared the impact of existing ABA, special nursery placements, and portage programs on a variety of aspects of the children's abilities. The latter two were selected because special nursery placement is a commonly occurring program offered to children with ASD, which has received little direct assessment...
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