TABLE 3.

Survival analysis using the Mantel–Cox test for the factors obtained from the individual concentrations of human milk oligosaccharides in colostrum and mature milk¹

		Outcomes
		Late-onset sepsis		Composite outcome2
Sample type	Factors	HR (95% CI)	P	HR (95% CI)	P
Colostrum (n = 99)
	1	1.00 (0.67, 1.49)	0.98	1.18 (0.85, 1.63)	0.31
	2	1.26 (0.87, 1.80)	0.21	1.30 (0.92, 1.84)	0.14
	3	0.63 (0.41, 0.97)	0.04	0.67 (0.46, 0.96)	0.03
Mature milk (n = 100)
	1	0.74 (0.45, 1.20)	0.22	0.71 (0.44, 1.14)	0.15
	2	0.96 (0.65, 1.44)	0.86	0.92 (0.62, 1.36)	0.67
	3	1.24 (0.83, 1.84)	0.29	1.24 (0.84, 1.82)	0.28

¹Proportional hazards were assumed after we tested for nonproportionality using the Schoenfeld residuals (P > 0.05). HRs were calculated using the Mantel–Cox test. Factors 1, 2, and 3 were generated independently for colostrum and mature milk through factor analysis. They summarize the concentrations of the 19 initial oligosaccharides. We predetermined 3 factors for each sample type with eigenvalues >1. No rotation was applied for those factors.

²Includes late-onset neonatal sepsis, necrotizing enterocolitis, and death by sepsis.