Inequities in the global representation of sites participating in large, multicentre dialysis trials: a systematic review

Abstract

BackgroundThe number of dialysis recipients is growing worldwide, making it important that the full range of patient populations are represented in randomised trials. As trial recruitment has not previously been examined at a global level, we compared the location of trial sites recruiting to large multicentre randomised controlled trials (RCTs) in dialysis to the global distribution of dialysis recipients.MethodsA systematic review (2007–2016) was conducted to identify RCTs enrolling ≥100 dialysis patients from ≥2 sites. The number and location of sites were extracted from manuscripts and trial registration. The proportion of sites from each International Society of Nephrology global region was divided by the proportion of the global dialysis population in that region to determine a ‘representation index’ (RI), where 1.0 indicated that the number of sites was proportionate to the number of dialysis recipients in that region.ResultsWe identified 180 RCTs, recruiting from 6172 sites in 54 countries. Eastern and Central Europe had the highest RI at 2.45. Other well-represented regions were Western Europe (2.20), North America (2.06), 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 (0.41), and South-East Asia and Oceania (0.62).ConclusionsRegions of the world with growing numbers of dialysis patients are poorly represented in large, multicentre RCTs. Efforts to boost trial participation in these regions are required to ensure that generalisable and relevant information is available to local healthcare providers.

Ethical Issues in the Design and Conduct of Pragmatic Cluster Randomized Trials in Hemodialysis Care: An Interview Study With Key Stakeholders

“…This lack of discussion within previous analyses is surprising given the established literature illustrating that participants recruited to trials testing hemodialysis interventions may not reflect the broader clinical population from which they are drawn 38,39 and broader inequities in hemodialysis care. [40][41][42] Notably, patients enrolled in hemodialysis trials have also been found to be younger and have fewer comorbidities than patients in the clinical setting, 43 with many trials systematically excluding patients above the age of 65.…”

Temporal changes in dialysate [Na+] prescription from 1996 to 2018 and their clinical significance as judged from a meta‐regression of clinical trials

“…19 Such selection bias favoring "healthy patients" is not unique to dialysis-related clinical trials-entirely concordant findings are seen in clinical trials within other medical subspecialties. [20][21][22][23][24][25][26] However, to illustrate the impact of this situation in the real world, an exercise can be undertaken using the dialysis registry data from New Zealand from As importantly, what is the optimal approach for hemodialysis providers? The overall picture suggests that they should not be continuing to decrease default dialysate [Na + ] without further evidence or assessment for benefit and harm.…”

“…The mortality rate in the studies was approximately half of that in the registry data to which it was compared (8.9 versus 18.6 deaths per 100 patient years) 19 . Such selection bias favoring “healthy patients” is not unique to dialysis‐related clinical trials—entirely concordant findings are seen in clinical trials within other medical subspecialties 20‐26 . However, to illustrate the impact of this situation in the real world, an exercise can be undertaken using the dialysis registry data from New Zealand from 1 January 1998 to 31 December 2017.…”

Poor Representation of Developing Countries in Editorial Boards of Leading Obstetrics and Gynaecology Journals

“…This is encouraging for the scientific research community since any untoward events can be monitored and rectified before widespread use leads to uncontrollable cascades. However, research representation in sample subsets is far from equitable (Algahtani et al 2018;Samalik et al 2022;Smyth et al 2019). The thalidomide tragedy needs no revisiting (Kim and Scialli 2011) and with the availability of preprint sites, virtual conferences and other collaborative mediums that permit the rapid dissemination of research findings, having equitable representation amongst patient populations before drawing research conclusions is more feasible than before.…”