A HABER1, B SMYTH2,3, K TRONGTRAKUL4, B TALBOT2, C HAWLEY5, V PERKOVIC2, M WOODWARD2,6, M JARDINE2,7
1Chelsea and Westminster Hospital, London, United Kingdom, 2The George Institute for Global Health, UNSW, Sydney, Australia, 3Sydney School of Public Health, University of Sydney, Sydney, Australia, 4Faculty of Medicine, Vajira Hospital, Navamindradhiraj University, Bangkok, Thailand, 5Princess Alexandra Hospital, Brisbane, Australia, 6The George Institute for Global Health, University of Oxford, Oxford, United Kingdom, 7Renal Unit, Concord Repatriation General Hospital, Sydney, Australia
Aim: To determine the global distribution of study sites participating in large multicentre randomised controlled trials (RCTs) recruiting people receiving maintenance dialysis.
Background: Large multicentre RCTs are essential to proving treatment effectiveness, but those conducted in one region may have limited generalisability or fail to address clinical questions of highest priority to dialysis patients and providers in other regions.
Methods: We systematically reviewed the literature for RCTs enrolling ≥100 dialysis patients from ≥2 sites published in 2007-2016, extracting data including site number and location from identified papers and associated trial registration. Sites were categorised according to the 10 International Society of Nephrology global regions. The proportion of sites in each region was divided by the proportion of global dialysis patients from that region to calculate a ‘representation index’ (RI) where 1.0 indicates that the proportion of sites is equal to that expected from the proportion of dialysis patients in the region.
Results: We identified 190 eligible multicentre RCTs including 58 countries and 6187 sites. The Eastern and Central Europe region had the highest RI at 2.45. Other well-represented regions were Western Europe (2.20), North America (2.07) and Russia and Newly Independent States (1.36). Africa had the lowest RI at 0.05, followed by South Asia (0.08), Latin America (0.15), Middle East (0.27), North East Asia (0.42) and South East Asia and Oceania (0.62).
Conclusions: Regions of the world with growing numbers of dialysis patients are poorly represented in large, multicentre RCT. Efforts to boost trial participation in these regions are required to ensure that generalisable and relevant information is available to local clinicians, patients and healthcare providers.
Dr Smyth is a nphrologist and PhD candidate at The George Institute for Global Health. His research interests include dialysis, especially randomised controlled trial methodology and evidence as well as patient reported outcomes in dialysis patients.