1. Division of Population Health, Health Services Research and Primary Care, University of Manchester, Manchester, UK
2. School of Nursing, Midwifery and Social Work, University of Manchester, Manchester, UK
3. Centre for Occupational and Environmental Health, University of Manchester, Manchester, UK
4. Primary Care & Health Sciences, Keele University, Keele, UK
5. Department of Health Sciences, University of York, York, UK
6. Social and Behavioral Sciences, Tilburg University, Tilburg, the Netherlands
7. Department of Psychology, University of Sheffield, Sheffield, UK
8. School of Social and Community Medicine, University of Bristol, Bristol, UK