This surprised me. I follow the literature from a distance, and I don't remember a landmark study that defined the clinically significant (rather than statistically significant) benefits of intense early intervention. I especially don't remember a study describing the kind of early intervention.
I figured I'd missed something, so I did a quick review and found these studies ...
- One-year follow-up of the outcome of a randomized ...[Child Care Health Dev. 2009]
- How can early intensive training help a genetic disorder?
- Cochrane review of parent-mediated early intervention (2003)
- Behavioural and developmental interventions for autism spectrum disorder: a clinical systematic review. (2008)
There's no significant new evidence, and damned little quality evidence of any kind to guide recommendations for early intervention of any kind by any party. The "conventional wisdom" about "intensive early intervention" appears to be more wishful thinking than evidence based.
This is damned frustrating. Intensive interventions strain financial and personal resources for society and families. In the absence of evidence we don't know how best to spend that money, time and energy -- on speech therapy, cognitive exercises, early education programs, adaptive sports, parental training, respite care, behavior modification programs, alternative communication strategies, cosmic ray therapy (ok, I made that one up) ...
Ok, now back to our regular programming.