Table 1.

Diagnostic scores on the ADOS and ADI-R

31 months43 months52 months38 months
    Communication (cutoff 2 or higher)4584
    Social interaction (cutoff 4 or higher)11131212
    Total (cutoff 7 or higher)15182016
    Stereotyped behaviors5463
    Social interaction (cutoff 10 or higher)23192422
    Communication (cutoff 7/8 or higher)13211813
    Restricted/repetitive/stereotypedbehavior (cutoff 3 or higher)4433
  • ADOS stands for Autism Diagnostic Observational Schedule (version G) (Lord et al., 2002) and ADI-R for Autism Diagnostic Interview-Revised (Lord et al., 1994). Both boys met criteria for a diagnosis of autism on both the tests at all time points. For a detailed description of the tests, see supplemental materials, available at