It does appear that children improve in functioning (as measured by a variety of outcome measures) with behavioural intervention. The majority of recent primary studies reviewed here document some improvement associated with intervention, however it remains to be determined if any one early and/or intensive intervention programme is more effective than another programme. The primary studies included in this Tech Brief cover a range of interventions and comparisons and it was not clear that the definition of intensive behavioural treatment, parent training or parent-managed behavioural therapy were uniform across individual studies evaluating similar approaches to early intervention. The intensity and duration of the intervention offered was only documented in some of the studies and sample sizes were mostly small. Given these and other limitations, the primary studies appraised generally provide only very preliminary evidence about the effectiveness of behavioural and skill-based early intervention. Nevertheless, two of these studies were graded as Level II according to the NHMRC hierarchy which reflects high level evidence.
- Parent-managed intensive behavioural interventions were not found to be as effective as clinic-based professionally directed programmes by Bibby et al. (2002), however a parent training intervention was more effective than usual care for improving communication.
- Intensive behavioural treatment may have a positive effect on measures of IQ, language expression and comprehension and communication (Eikeseth et al. 2002) and one recent study has suggested intensive behavioural intervention may be more effective than parent training.
- Early intervention that utilises a social-developmental approach may be an effective treatment model.
Direct empirical evidence that early compared to later intervention has a specific positive benefit is not yet available, at best there appears to be consensus among experts in the field that developmental principles support the notion of early intervention. More research in this area is needed and the conclusions of this Tech Brief should be revisited as the results, particularly of current and ongoing trials become available.