[1] Univ Birmingham, Inst Appl Hlth Sci, Birmingham B15 2TT, W Midlands, England
[2] Univ Oxford, Nuffield Dept Primary Care Hlth Sci, Radcliffe Observ Quarter, Radcliffe Primary Care Bldg,Woodstock Rd, Oxford OX2 6GG, England
[3] Univ Greenwich, Fac Educ & Hlth, Dept Family Care & Mental Hlth, London, England
[4] Univ Stirling, Inst Social Mkt, Stirling FK9 4LA, Scotland
[5] Univ Geneva, Fac Med, Geneva, Switzerland