Ethics of human subject participation
This study was conducted according to the guidelines laid down in the Declaration of Helsinki, and all procedures involving research study participants were approved by the Hunter New England Human Research Ethics Committee (17/08/16/4·07), the NSW Department of Education (SERAP2017457) and the relevant Catholic Diocese Ethics Committee (18/12/2018). Written informed consent was obtained from all subjects/patients (i.e. principals at participating schools).