A Duke University review of a survey involving more than 10,000 American teenagers reveals that more than half of adolescents with psychiatric disorders receive no treatment of any sort. Moreover, when treatment does occur, the providers are rarely mental health specialists, said Dr. E. Jane Costello, a Duke University professor of psychology and epidemiology, the study leader. The country's mental health system has come under scrutiny in recent years following a string of mass shootings in which mental illness seems to have played…