Funding for this research was provided by:
National Institute of Mental Health (ZIA-MH-002868)
Received: 3 August 2017
Accepted: 19 December 2017
First Online: 5 January 2018
Ethics approval and consent to participate
: Informed consent was obtained for participants, who were enrolled in a longitudinal natural history study of autism approved by an NIH Institutional Review Board (06-M-0102).
: Not applicable.
: The authors declare that they have no competing interests.
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