[1] Cardiff Univ, Ctr Trials Res, Neuadd Meirionnydd,Heath Pk, Cardiff CF14 4YS, Wales
[2] Cardiff Univ, Sch Med, PRIME Ctr Wales, Div Populat Med, Cardiff, Wales
[3] Cardiff Univ, Ctr Dev & Evaluat Complex Intervent Publ Hlth Imp, Cardiff, Wales
[4] Newcastle Univ, Natl Inst Hlth Res Newcastle Vitro Diagnost Coope, Newcastle Upon Tyne, Tyne & Wear, England
[5] Newcastle Univ, Translat & Clin Res Inst, Newcastle Upon Tyne, Tyne & Wear, England
[6] Newcastle Tyne Hosp, NHS Fdn Trust, Northern Med Phys & Clin Engn, Newcastle Upon Tyne, Tyne & Wear, England
[7] Newcastle Freeman Hosp, Newcastle Tyne NHS Hosp Trust, Dept Urol, Newcastle Upon Tyne, Tyne & Wear, England