Received: 3 July 2019
Accepted: 17 March 2020
First Online: 15 April 2020
Ethics approval and consent to participate
: This study was granted ethical approval by the Hunter New England Human Research Ethics Committee (HREC) (Approval number: 16/09/21/4.05). Thereafter, the remaining sites had site-specific applications submitted to their respective HRECs. Ethics approval was also provided by the Aboriginal Health and Medical Research Council (Approval number: 1232.16). Approval for access to key datasets was granted by the Justice HREC (coronial data; approval number: CF/17/10447), and the South-Eastern Sydney HREC (ambulance data; approval number: 16.09/21/4.06).
: The manuscript contains no individual person’s data in any form as is standard for a protocol study, so not applicable.
: The authors declare that they have no competing interests.