[1] Univ Glasgow, Sch Hlth & Wellbeing, Glasgow, Scotland
[2] NHS Lothian, Western Gen Hosp, Edinburgh Canc Ctr, Edinburgh, Scotland
[3] Univ St Andrews, Sch Med, St Andrews, Fife, Scotland
[4] Univ Glasgow, Sch Hlth & Wellbeing Gen Practice & Primary Care, Glasgow G12 8QQ, Scotland