Funding for this research was provided by:
National Institutes of Health (R21HG007687)
Instituto de Salud Carlos III Fondo de Investigación Sanitaria (PI 14/0582)
Received: 4 August 2017
Accepted: 13 February 2018
First Online: 27 February 2018
Ethics approval and consent to participate
: The GAIT2 study was performed according to the Declaration of Helsinki and adult subjects gave written informed consent for themselves and for their minor children. The GAIT2 study was reviewed and approved by the Institutional Review Board of the Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
: Not applicable.
: The authors have declared that no competing interests exist.
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