Table 4.

Correlation of resistive Index (RI) with histological grades (n=60).

Histological grades	N	Mean RI	SD	Variance	Sum of squares	df	F	Sig.
Mild fibrosis (<25%)	43	0.7051	0.09615	Between grades of fibrosis	0.190	2	10.17	0.000
Moderate fibrosis (25–50%)	13	0.7923	0.10725
				Within grades of fibrosis	0.532	57
severe fibrosis (>50%)	4	0.9000	0.04320
Total	60	0.7370	0.11060		0.722