Mean, standard deviation (SD), and coefficient of variation (CV) of serum phosphorus, calcium, and iPTH of MHD patients by CAC score tertile.

Values expressed as mean ± SD. SD and CV were calculated from the past 6 follow-up values (April 2009 to July 2010). The mean was the average of patients' SD or CV which depended on the variations of patients over time. The SD showed how much variation from the average existed in one group.MHD, maintenance hemodialysis; CAC, coronary artery calcification; SD, standard deviation; CV, coefficient of variation; PTH, parathyroid hormone.Data compared by univariate ordinal logistic regressions;*P