The development of the new edition began with a conference in 1999, and proceeded with the formation of a Task Force in 2007, which developed and field-tested a variety of new classifications. In most respects DSM-5 is not greatly changed from DSM-IV-TR. Notable changes include dropping Asperger syndrome as a distinct classification; loss of subtype classifications for variant forms of schizophrenia; dropping the "bereavement exclusion" for depressive disorders; a revised treatment and naming of gender identity disorder to gender dysphoria, and removing the A2 criterion for posttraumatic stress disorder (PTSD) because its requirement for specific emotional reactions to trauma did not apply to combat veterans and first responders with PTSD.