Funding for this research was provided by:
National Institute of Health Research (12/153/60)
Education Endowment Foundation (no award number)
Received: 19 March 2020
Accepted: 14 August 2020
First Online: 10 September 2020
Change Date: 23 September 2020
Change Type: Correction
Change Details: An amendment to this paper has been published and can be accessed via the original article.
Ethics approval and consent to participate
: Ethical approval was obtained by the University College London ethics committee (ref5248/001). Written, informed consent was obtained from head teachers for random allocation. Students, staff, and facilitators were given information sheets and consent forms and had the opportunity to opt-out.
: Not applicable
: The authors declare that they have no competing interests.