Funding for this research was provided by:
National Institute on Aging (K24 AG049077-01A1)
Received: 2 December 2019
Accepted: 11 January 2020
First Online: 14 February 2020
Compliance with ethical standards
: All authors declare that they have no conflict of interest.
: Use of this data set was approved by the Institutional Review Board of Johns Hopkins University.
: While participants in the original NHATs study provided individual informed consent, a waiver was granted for this secondary data analysis with a limited data set.
: All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation, both institutional and national. No animals were involved in this research.