Funding for this research was provided by:
National Center for Injury Prevention and Control (R49CE003095)
National Institute for Occupational Safety and Health (U54 OH007548)
Received: 27 March 2020
Accepted: 11 May 2020
First Online: 1 July 2020
Ethics approval and consent to participate
: This study was determined to be exempted from Human Subject Office review because the data are publicly available and de-identified. This determination was made by the University of Iowa Human Subject Office.
: Not applicable.
: Authors have no competing interests.