Table 3.

Change in percentages of urinary arsenic metabolites and other arsenic biomarkers between two visits^a

	Sirajdikhan			Pabna			All mothers
	Median change	Mean	p-valuea	Median change	Mean	p-value	Median change	Mean	p-value
	(5th–95th percentile)	change		(5th–95th percentile)	change		(5th–95th percentile)	change
iAsIII%b	0 (−10.6, 8.5)	−0.7	< 0.01	− 0.1 (− 15.7, 9)	−2.6	< 0.01	0 (− 13.9, 8.7)	− 1.6	< 0.01
iAsV%	0 (− 13.8, 18.3)	0.8	0.09	0 (−14.2, 13.8)	0.2	0.38	0 (− 14.2, 16.6)	0.5	0.56
iAs%	0 (−16.3, 17.6)	0.1	0.27	−2.7 (−15.9, 12.3)	−2.5	< 0.01	−1.4 (− 16.2, 15.1)	−1.1	< 0.01
MMA%	0.4 (−9.1, 9)	0.5	< 0.01	−0.3 (−8, 5.7)	− 0.6	< 0.01	0.1 (− 8.6, 7.3)	0	0.91
DMA%	−0.2 (−22.7, 21)	− 0.6	0.52	3.3 (−12.2, 20.6)	3.1	< 0.01	1.8 (−19.7, 20.8)	1.1	< 0.01
log (unadjusted U-As)c	0.6 (−1.8, 2.8)	0.5	<  0.01	−0.1 (−2.2, 2)	− 0.1	0.03	0.3 (−2, 2.5)	0.2	< 0.01
log(U-creatinine)	0.3 (−1.7, 2.1)	0.3	<  0.01	−0.2 (−2.1, 1.5)	− 0.3	<  0.01	0.1 (− 1.9, 1.9)	0.1	0.07
log (adjusted U-As)	0.6 (−1.8, 2.8)	0.5	< 0.01	−0.1 (−2.2, 2)	− 0.1	< 0.01	0.3 (− 2, 2.5)	0.2	< 0.01
log (DW-As)d	0 (−3.5, 2.5)	0	0.89	0 (−1.3, 2)	0.2	< 0.01	0 (−2.7, 2.5)	0.1	0.05
log(T-As)	−0.4 (−1.8, 1.1)	− 0.4	< 0.01	− 0.3 (− 1.1, 0.7)	−0.3	< 0.01	− 0.4 (− 1.5, 0.8)	−0.4	< 0.01

^a The units of iAs^III%, iAs^V%, iAs%, MMA% and DMA% are all “%”. The unit of unadjusted U-As, U-creatinine, adjusted U-As, DW-As and T-As are μg/L, mg/dL, μg/g-creatinine, μg/L and μg/g, respectively

^b Wilcoxon signed rank test p-values for the first five variables, conditional on Sirajdikhan site (N = 782), Pabna site (N = 661), and all mothers (N = 1443)

^c Paired t-tests of differences between visit 1 and visit 2, conditional on Sirajdikhan site (N = 782), Pabna site (N = 661), and all mothers (N = 1443)

^d Paired t-tests of differences between visit 1 and one-month post-partum, conditional on Sirajdikhan site (N = 577), Pabna site (N = 573), and all mothers (N = 1150)