Table 2.

Comparison of serum bilirubin levels between two groups at different time points(umol/L)( ± s)

	the NEC group	the non-NEC group	t	p
CB at birth	12.64±2.68	13.39±2.87	-1.271	0.206
CB 1 week after birth	17.11±4.48	15.63±3.75	1.777	0.078
CB 2 weeks after birth	19.25±11.63	15.47±4.12	2.483	0.015
time*group	F = 4.085, P = 0.019
TB at birth	52.27 ± 24.23	52.05 ± 21.63	0.046	0.963
TB 1 week after birth	140.56 ± 42.44	121.67 ± 39.52	2.269	0.025
TB 2 weeks after birth	109.15 ± 32.94	100.83 ± 35.71	1.173	0.243
time*group	F = 3.306 P = 0.039

CB: conjugated bilirubin; TB: total bilirubin