Lee, Yoonjoo http://orcid.org/0000-0002-2697-3690
Hofferth, Sandra L.
Funding for this research was provided by:
National Institute of Child Health and Human Development (R01-HD053654)
National Institute of Child Health and Human Development (R24-HD041041)
Article History
First Online: 28 August 2017
Compliance with Ethical Standards
:
: The authors declare that they have no competing interests.
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
: Informed consent was obtained from all individual participants included in the study.