**2. What constitutes EIBI?**

early intervention is the best response to the treatment of ASD. Providing treatment of symp‐ toms immediately will result in more favourable treatment outcomes (Dawson, 2008; Howlin, Magiati & Charmin, 2009; Reichow & Wolery, 2009). Many have argued that this early inter‐ vention will allow greater opportunities for a young child to move towards a more typical de‐ velopmental trajectory because of malleability or plasticity of the developing young brain (see for example Dawson 2008). From a learning theory account, teaching new behaviour or re‐ placement behaviour to a very young child presenting with behavioural deficits or excesses, will result in desirable consequences that impacts behavioural repertoires and learning history from the outset. In this way early intervention for the condition may affect the onset of addi‐ tional secondary problem behaviours which are often not seen at diagnosis. As such these may

While a consensus that early intervention for ASD exists amongst researchers in this field, many argue that the actual approach applied during this critical period may be pivotal in producing the greatest outcomes and ensuring the best chance of attaining a typical devel‐ opmental trajectory. Over the past four decades, interventions based on the science of ABA have been thoroughly evaluated and shown to produce effective outcomes in targeting many of the challenges presented within this condition. Moreover, behavioural interven‐ tions drawn from this science can produce substantial gains in cognitive, adaptive and social behaviours in this population (Dillenberger, 2011). Indeed, this approach is internationally recognised as the most effective basis for treatment for children with ASD (Larsson, 2005).

Improving the core symptoms of ASD is a common goal for parents and professionals. Re‐ ports of large improvements in this condition have been documented. For example Smith (1999) provided a summary of published peer-reviewed studies involving seven independ‐ ent groups of researchers documenting dramatic gains when early intervention was applied. Importantly however, in all studies reviewed, interventions were underpinned by ABA methodology and theory and were intensive involving a range of 15 to 40 hours per week across studies. This approach to autism treatment, known as Early Intensive Behavioural In‐ tervention (EIBI) has generated much discussion and excitement, and continues to gather momentum impressing on policy makers the urgency of effective and substantiated provi‐

Studies on EIBI have reported the following gains: (1) average increases of approximately 20 points in IQ (e.g., Harris, Handleman, Gordon, Kristoff, & Fuentes, 1991; Lovaas, 1987; Sheinkopf & Siegal, 1998) (2) increases in standardised test scores (Anderson, Avery, DiPie‐ tro, Edwards, & Christian, 1987; Birnbrauer & Leach, 1993; Hoyson, Jamison, & Strain, 1984; McEachin, Smith, & Lovaas, 1993; Strauss et al. 2012), (3) increased gains in adaptive behav‐ iour (Eldevik et al., 2012; Strauss et al., 2012); (4) improved language scores (Eldevik et al., 2012; Strauss et al. 2012); (5) the need for less supports in school (Fenske, Zalenski, Krantz, & McClannahan, 1985; Lovaas, 1987), (6) reduced autism symptomotology (Eikeseth et al,. 2012) and (7) decreased challenging behaviour (Fava et al., 2012). Dillenberger (2011) refers to the increasing evidence of clinical, social and financial efficiency of intensive behavioural intervention in autism treatment which has resulted in "legally enshrining" such interven‐ tion in North America. For example, the Autism Treatment Acceleration Act (2010) requires

be minimised or even prevented (Mundy, Sullivan & Mastergeorge, 2009).

568 Recent Advances in Autism Spectrum Disorders - Volume I

sion for individuals and families affected by the condition.

EIBI is based on the scientifically applied principles of learning and behaviour, and has the dis‐ cipline of behaviour analysis (Cooper, Heron, & Heward, 2007) at its core. The approach gener‐ ally targets preschool children and is provided intensively, often in a 1:1 student/teacher ratio, for 20-50 hours per week. Dawson (2008) and Green (1996) summarise many of the common and conspicuous features of successful EIBI programs. These include the following:


According to Dawson (2008): *"When these features are present, results are remarkable for up to 50% of children"* (p.790).

It is important to note that EIBI draws from the bedrock of a science- Applied Behaviour Analysis (ABA). This science constitutes over 300 procedures (Greer, 2002; Steege, Mace, Perry, and Longenecker, 2007) each of which have been tested and demonstrated to produce behaviour change. The careful selection and application of these procedures to treat the be‐ havioural symptoms of autism delivered within the scientific framework of ABA (outlined in Baer, Wolf & Risley, 1968; 1987) is what defines an EIBI approach. It is critical to recognise how ABA and EIBI are interwoven because the science of ABA and the various behaviour change strategies therein, have a very long history of substantiated documentation (see for example Matson, Benavidez, Compton, Paclawskyj, & Baglio, 1996, who reviewed behavior‐ ally based treatments for autism over a 16-year span).

The searches were carried out using the terms "early intensive behavioural intervention AND autism", and "intensive behavioural intervention AND autism". The inclusion criteria were largely in line with those of Reichow (2012). Studies were reviewed if they included a treatment group who received EIBI and an alternate-treatment control group who received either no treatment, a different treatment or EIBI provided at different intensity levels. Only studies including children with ASD were reviewed. Each study was required to involve original research that was written in English and published in a peer reviewed journal. In the interest of clarity we grouped published investigations under the following headings: Studies published before 2000 (4 studies), studies published from 2000-2010 (12 studies) and studies published between 2011-2012 (5 studies). We provide a summary of factors associat‐ ed with each published paper including intake characteristics of participants, outcome measures employed, specific treatment characteristics and group differences following inter‐

Early Intensive Behavioural Intervention in Autism Spectrum Disorders

http://dx.doi.org/10.5772/54274

571

Lovaas (1987) conducted the first evaluation of EIBI for children with Autism. The outcomes of 19 children receiving EIBI, for a minimum of 40 hours per week, were compared to those of two control groups. The first control group, consisting of 19 children, received low inten‐ sity (10 hours or less) behavioural intervention and the second control group, consisting of 21 children, received TAU. After two years of treatment, 47% of the EIBI group achieved IQ scores in the normal range and were enabled to integrate fully into mainstream educational settings while only 2% of children in the control group achieved similar outcomes. In this case, almost half of children in the EIBI appeared to recover from their diagnosis of autism.

Birnbauer and Leach (1992) compared the outcomes of nine children receiving EIBI and five children in a control group (no treatment). Children in the EIBI group received an average of 18.7 hours of EIBI per week delivered by trained volunteers in their homes. Children in the EIBI group achieved significantly higher non-verbal IQ scores and language levels. Four of the nine children in the EIBI group achieved IQ scores within the normal range following treatment.

Smith et al. (1997) compared the outcomes of 11 children receiving EIBI to 10 children who received a low intensity behaviour intervention. Children in the high intensity EIBI group received at least 30 hours of clinician-delivered treatment each week while the low intensity group received 10 hours of clinician-delivered behavioural intervention each week. At fol‐ low-up, the children in the EIBI group showed greater increases in IQ and expressive lan‐

Sheinkopf and Siegel (1998) evaluated the outcomes of 11 children receiving EIBI and 11 children receiving Treatment as Usual (TAU). EIBI was delivered by parents, supervised by clinicians, for 27 hours each week. Children in the control group received 11.1 hours of TAU in a school setting each week. Following treatment, the EIBI group achieved significantly higher IQ scores and significantly lower scores on a measure of symptom severity than the

vention. The following sections provide a synopsis of all studies identified.

**4. Studies published before 2000 (4 Studies)**

guage than children in the control group.

control group.
