The field of nephrology, including renal replacement therapy, is insufficiently supported by evidence-based medicine.1-3 However, for hemodiafiltration, there is no lack of randomized controlled evidence,4-6 but the validity of the findings is disputed due to methodological concerns and clinical practice weaknesses, such as not achieving planned substitution volume.7,8 There are also more meta-analyses on hemodiafiltration than randomized controlled trials (RCTs).9-13 Even after the recent individual-participant data meta-analysis of RCTs that took most issues into account and showed benefit for hemodiafiltration, the debate continues.