Funding for this research was provided by:
The Children's Hospital of Philadelphia Wallace Chair of Pediatrics
Center for Disease Control
Text and Data Mining valid from 2019-01-01
Received: 25 September 2018
Accepted: 2 January 2019
First Online: 24 January 2019
Compliance with Ethical Standards
: The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention, US Department of Health and Human Services.
: The authors declare that they have no conflicts of interest.