Clark, David E.
Black, Adam W.
Skavdahl, David H.
Hallagan, Lee D.
Article History
Received: 15 January 2018
Accepted: 6 March 2018
First Online: 9 April 2018
Ethics approval
: The Maine Medical Center Institutional Review Board declared this project (“NTDB outcome studies”, 1056409-1) exempt from review on April 14, 2017.
: N/A.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.