RCT	Randomized controlled trial
RKF	Residual kidney function
1-WHD	Once-weekly HD with low-protein diet (0.6 g/kg/day), and KAs (0.12 g/kg/day) on non-dialysis days, and a regular-protein diet (1.0–1.2 g/kg/day) on dialysis days
2-WHD	Twice-weekly HD with a regular-protein diet (1.0–1.2 g/kg/day)
KA	Keto-analogues
QoL	Quality of life
β2M	β2-microglobulin