Which of the following is not true about the autistic specific disorder :

Autistic disorder:- Pervasive developmental disorders. Also called autistic spectrum disorders, cluster of syndromes that share marked abnormalities in the development of social and communicative skills. Symptoms: Qualitative impairment in social interaction as manifested by two of the following- impairment in use of multiple non verbal behaviors( eye gaze, facial expression, body postures) , failure to develop peer relationships, lack of sharing of enjoyment, lack of social or emotional reciprocity. Qualitative impairment in communication in at least one of the following areas- delay or total lack of spoken languages, marked impairment in the ability to initiate or sustain a conversation with others, stereotyped or repetitive use if languages and lack of varied spontaneous play. Restricted repetitive and stereotyped patterns of behaviors, interests, and activities as manifested by preoccupation with one or more restricted patterns of interests; inflexible adherence to nonfunctional routines or rituals ; repetitive motor mannerisms( such as rocking, hand flipping, finger flicking) and preoccupation with pas of objects. Intelligence is variable. Reference: GHAI Essential pediatrics, 8th edition