[1] Royal Liverpool Univ Hosp, Intens Care Unit, Prescot St, Liverpool L7 8XP, England
[2] Univ Liverpool, Inst Life Course & Med Sci, Liverpool, England
[3] Univ Liverpool, Inst Populat Hlth, Dept Primary Care & Mental Hlth, Liverpool, England
[4] Liverpool Univ Hosp NHS Trust, Clin Hlth Psychol Serv, Liverpool, England
[5] Univ New England, Sch Psychol, Armidale, NSW, Australia
[6] Royal Victoria Hosp, Reg Intens Care Unit, Belfast, North Ireland
[7] Queens Univ Belfast, Wellcome Wolfson Inst Expt Med, Belfast, North Ireland
[8] Univ Liverpool, Liverpool Ctr Cardiovasc Sci, Liverpool, England
[9] ICUsteps Char, London, England