In the world of mental health, the Diagnostic and Statistical Manual of Mental Disorders is more or less the bible. Doctors use the DSM's definitions to diagnose depression, stuttering, fetishism, schizophrenia and more than 300 other conditions. Insurance companies use it to justify reimbursements; without a DSM code, mental-health patients usually don't get a dime. And the manual carries enormous cultural heft: when it stopped listing homosexuality as a mental disorder--after a 1974 psychiatrists' debate in which being gay was deemed sane by a vote of 5,854 to 3,810--gay rights received a crucial boost.
So naturally, on Dec. 1, when the...