Funding for this research was provided by:
National Institute of General Medical Sciences (8 P20 GM103440-11)
Received: 16 November 2016
Accepted: 2 July 2017
First Online: 11 July 2017
Ethics approval and consent to participate
: This study was approved by the University of Nevada, Las Vegas Institutional Review Board; excluded as “Not Human Subjects Research” under Protocol # 798947-1. Data use agreements were obtained from California and Texas. The mortality data that support the findings of this study were obtained by special permission from the State of California, Department of Public Health, Center for Health Statistics and Informatics, Health Information and Research Section and the State of Texas, Texas Department of State Health Services, Center for Health Statistics.
: Not applicable.
: The authors declare that they have no competing interests.
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