Published on in Vol 20, No 6 (2018): June

1 Bristol Interaction Group, Faculty of Engineering, University of Bristol, Bristol , GB
2 Centre for Academic Mental Health, Population Health Sciences, Bristol Medical School, University of Bristol, Bristol , GB
3 National Institute for Health Research Bristol Biomedical Research Centre , University Hospitals Bristol NHS Foundation Trust and University of Bristol, Bristol , GB
4 School of Computer Science , University College Dublin, Dublin , IE
*these authors contributed equally