I'm assuming you have children with some level of verbal development in mind for this question. Other options might include Social Communication Questionnaire, the Autism Spectrum Screening Questionnaire. The SCQ has nice psychometric properties but doesn't add much prediction to a clinical diagnosis of ASD if you're using gold-standard observation systems like the ADOS-2. The Journal of Child Psychology and Psychiatry or the Journal of the American Acadamy of Child and Adolescent Psychiatry published a study in the last year informing this.
Autism and Mental Retardation in patients is hard to differentiate between one and the other. Does amyloid plaque formation occur in both cases? - ResearchGate. Available from: https://www.researchgate.net/post/Autism_and_Mental_Retardation_in_patients_is_hard_to_differentiate_between_one_and_the_other_Does_amyloid_plaque_formation_occur_in_both_cases [accessed Jan 25, 2016].
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