[1] Univ Lincoln, Sch Hlth & Social Care, Lincoln LN6 7TS, England
[2] Univ Lincoln, Sch Social & Polit Sci, Lincoln LN6 7TS, England
[3] Univ Lincoln, Sch Hlth & Social Care, Community & Hlth Res Unit, Primary & Prehosp Healthcare, Lincoln LN6 7TS, England
[4] Kingston Univ, Emergency Cardiovasc & Crit Care Res Grp, 6th Floor,Hunter Wing,Cranmer Terrace, London SW17 0RE, England
[5] St Georges Univ London, 6th Floor,Hunter Wing,Cranmer Terrace, London SW17 0RE, England