Article History
Received: 18 March 2020
Accepted: 19 August 2020
First Online: 21 September 2020
Ethics approval and consent to participate
: Not applicable.
: Not applicable.
: Dr. Guohua Li serves as editor-in-chief of Injury Epidemiology. He was not involved in the review or handling of this manuscript. The authors declare that they have no competing interests.