The terminology of autism has changed a great deal over the past 100 years as researchers gained knowledge about the condition. The current diagnostic criteria, in place since the fifth edition of the Diagnosis and Statistical Manual of Mental Disorders (DSM-5) was published in 2013, reclassifies all previously distinct autism-related diagnoses under one umbrella, that of autism spectrum disorder (ASD). The word spectrum describes the wide variety of behaviors and other symptoms at differing severity levels in people with autism. ASD describes symptoms in two areas: Persistent deficits in social communication and social interaction Restricted, repetitive patterns of behavior, interests, or activities The criteria also provide a basis for rating the severity of symptoms in both areas as 1 (requiring support), 2 (requiring substantial support), or 3 (requiring very substantial support). Social (pragmatic) communication disorder (SCD) is a newer, separate ...