. 2017 Mar 29;12(3):e0173669. doi: 10.1371/journal.pone.0173669

Table 1. Clinical characteristics of women choosing NIPT, CVS and amniocentesis.

	Total population (n = 254)	NIPT (n = 186)	CVS (n = 39)	amniocentesis (n = 29)	p value (anova or chi square test)	p value (NIPT VS CVS)	p value (CVS VS amniocentesis)	p value (NIPT VS amniocentesis)
Maternal age, mean (SD)	35.7 (5.2)	36.2 (5.2)	35.2 (4.8)	33.3 (5.3)	0.015^*	0.544	0.314	0.018^*
Gestational age, mean (SD)	100.1 (12.9)	98.9 (11.5)	92.1 (4.3)	118.2 (12.5)	0.000^**	0.002^**	0.000^**	0.000^**
Counseling day
Monday—Tuesday, n(%)	169 (66.5%)	139 (74.7%)	14(35.9%)	16 (55.2%)	0.000^**	0.000^*	0.135	0.029^*
Wednesday—Friday, n(%)	84 (33.5%)	47 (25.3%)	24 (64.1%)	13 (44.8%)	0.000^**	0.000^*	0.135	0.029^*
Trimester of screening
the first trimester screening, n(%)	218 (85.8%)	169 (90.9%)	39 (100%)	10 (34.5%)	0.000^(0.000^ Fisher’s exact)	0.050 (0.049^* Fisher’s exact)	0.000^(0.000^ Fisher’s exact)	0.000^(0.000^ Fisher’s exact)
the second trimester screening, n(%)	36 (14.2%)	17 (9.1%)	0 (0.0%)	19 (65.5%)	0.000^(0.000^ Fisher’s exact)	0.050 (0.049^* Fisher’s exact)	0.000^(0.000^ Fisher’s exact)	0.000^(0.000^ Fisher’s exact)
Serum screening risk score, mean (SD)	0.022 (0.041)	0.019 (0.035)	0.041 (0.068)	0.018 (0.021)	0.014^**	0.137	0.054	0.863

*p<0.05;

**p<0.01