Just as a side note lets also consider that they are basing this on the fact that over 30 years there has been a "significant" whereas no mention of the increase in medical knowledge to identify a variety of problems including autism as increased over the same time frame worldwide (worldwide as they mention in the paper this is based not only in the US but other countries seeing an "increase as well) where 30 years ago bi-polar would have been recognized as schizophrenia and to what degree the patient had it by probably would have resulted in either hospitalization, electro-shock or even lobotomy rather than pharmaceutical and environmental changes to retard or even restrict person issues and personal and external danger situations.