. 2019 Nov;215(5):639–646. doi: 10.1192/bjp.2019.3
© The Royal College of Psychiatrists 2019
This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited.