Dispute grows over revisions to diagnostic handbook.
Psychologist David Elkins had modest ambitions for his petition. He and his colleagues were worried that proposed changes to an influential handbook of mental disorders could classify normal behaviours as psychological conditions, potentially leading to inappropriate treatments. So they laid out their concerns in an open letter, co-sponsored by five divisions of the American Psychological Association in Washington DC. "I thought, 'Well, maybe we'll get a couple or maybe 30 signatures'," says Elkins, an emeritus professor at Pepperdine University in Malibu, California.
But the letter, posted online on 22 October (go.nature.com/uhmvqq), touched a nerve. Within 10 days more than 2,800 people had signed it, many identifying themselves as mental-health professionals