Statistical analyses
According to the PIVOTAL trialContinuous variables were expressed as mean ± standard deviation (SD) or median and IQR and compared using unpaired We presented time to withholding IV iron and time to iron rescue therapy between groups using the Kaplan–Meier curve and compared it with Cox proportional hazard models. Mean cumulative doses of IV iron between groups were compared with linear random-intercept model. The patterns of protocol compliance were presented and compared with exact probability test. Moreover, we performed post-hoc subgroup analyses to assess whether sub-populations (defined using median values of baseline Hb, ferritin, and TSAT) may have affected the IV iron therapy withholding rate. And we also test whether certain clinical features may influence the difference in ESA doses.All 