Table 5. Calcium mass balances.

		A1.5	A1.25	C1.5	P-value#	Post-hoc (p-value, pairwise)*
						1	2	3
Calcium mmol/treatment	Total	5.67 [0.59; 9.54]	-2.4 [-6.19; 1.78]	-2.00 [-5.25; -0.18]	<0.001	<0.001	<0.001	0.91
	Diffusive	6.4 [3.1; 10.2]	-1.80 [-5.8; 3.4]	-1.60 [-3.6; 1.8]	<0.001	<0.001	<0.001	0.88
	Convective^	-3.45 [-4.165; -1.62]	- 2.84 [-3.33; -1.25]	-2.90 [- 3.64; -1.42]	<0.01	0.03	0.11	0.18
	Correlation (r; p-value)	-0.08; 0.74	-0.15; 0.95	-0.03; 0.91

Note: Data are expressed as median with 25^th and 75^th percentile.

^Patients without ultrafiltration during dialysis were left out.

^#P-values were calculated with Friedman test.

*Post hoc p-values were calculated with Wilcoxon Signed Rank test as pairwise comparisons and a p-value <0.017 was considered statistically significant based on Bonferroni correction. Correlation is between the delta calcium mass balance and delta T₅₀, calculated with Spearman rho (showed as correlation; p-value). A1.5 = acetic-acid dialysate with 1.50mmol/l calcium, A1.25 = acetic-acid dialysate with 1.25mmol/l calcium, C1.5 = citric-acid dialysate with 1.50mmol/l calcium. 1 = A1.5 vs. A1.25; 2 = A1.5 vs. C1.5; 3 = A1.25 vs. C1.5.