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Table 2 The analysis methods for the secondary outcomes

From: Rationale and study design of a randomized controlled trial for development of a treatment strategy for chronic kidney disease–mineral and bone disorder by multilateral mechanism of etelcalcetide hydrochloride (the DUET study)

Secondary outcomes The analysis method for the secondary outcomes
 1) The proportion of achievement of 60 ≤ iPTH ≤ 240 pg/dL after 12 weeks of treatment
 2) The proportion of achievement of more than a 50% reduction in iPTH levels after 12 weeks of treatment
 3) The proportion of achievement of more than a 30% reduction in iPTH levels after 12 weeks of treatment
 4) The proportion of achievement of more than a 30% reduction and 60 ≤ iPTH ≤ 240 pg/dL after 12 weeks of treatment
• Calculate the achievement proportions of the targets 1 to 4 at 12 weeks after administration, and 95% confidence intervals (CI) based on the binomial distribution for each treatment group.
• Compare these achievement proportions between the groups treated with etelcalcetide (group E+D and group E+Ca) and the control group (group C) by logistic regression analysis with iPTH, Ca, and P as covariates.
• When a statistical significant difference is obtained, compare the achievement proportion between group E+D and group E+Ca by logistic regression analysis.
 5) Changes in iPTH levels after 2, 4, 6, 8, 10, and 12 weeks of treatment relative to the baseline
 6) Changes in CPP and FGF23 levels after 6 and 12 weeks of treatment relative to the baseline
 7) Changes in calcium, phosphate, calcium-phosphate product, and magnesium levels after 2, 4, 6, 8, 10, and 12 weeks relative to the baseline
 8) Changes in BAP and TRACP-5b levels after 1 year of treatment relative to baseline
 9) Changes in aortic calcification before and after observation
• Calculate the adjusted mean and the 95% CI for changes at each time point by a linear mixed model with each treatment group, time point, and interaction of the treatment group and time point as the fixed effects.
• Compare between treatment groups using a linear mixed model with values of each index at baseline, treatment groups, time points, interaction between treatment groups and time points as the fixed effects and changes of each index as response variables.
• Compare changes of each index among treatment groups at each time point using the Tukey-Kramer method to correct for multiplicity.
 10) Normalized proportion of hypocalcemia induced by etelcalcetide between group E+D with group E+Ca • When hypocalcemia occurs in the group E+D and group E+Ca, calculate the normalized proportions with 95% confidence intervals (CI) based on binomial distribution for each treatment group.
• Compare normalized proportions between group E+D and group E+Ca using logistic regression analysis with iPTH, Ca, and P as covariates.