Received: 16 May 2019
Accepted: 4 December 2019
First Online: 8 January 2020
Ethics approval and consent to participate
: No subjects were interviewed, observed or exposed to any interventions are part of this study. No ethical review was sought by the authors for this literature synthesis.
: not applicable.
: The authors are full time employees of NSW Health. The authors declare that they have no competing interests.