Table 2.

Association of E-NAOI with maternal and infant characteristics

Risk factor	No. of infants	(%)	No. infants with E-NAOI event	E-NAOI rate (%)	Adjusted relative risk (RR)* of E-NAOI among births with this characteristic (95% CI)
Maternal characteristics
Age: <20 years	17 928	3.71	1064	5.93	0.96 (0.89 to 1.02)
Age: 20–34 years	3 67 164	75.88	19 119	5.21	Reference
Age: ≥35 years	98 757	20.41	5877	5.95	1.09 (1.05 to 1.13)
Primiparous	1 76 472	36.46	10 860	6.16	1.29 (1.25 to 1.32)
Multiparous	3 07 535	63.54	15 200	4.94	Reference
Infant characteristics
Female	2 35 702	48.70	10 991	4.66	Reference
Male	2 48 242	51.30	15 068	6.07	1.32 (1.28 to 1.35)
Term	4 50 454	93.07	13 978	3.10	Reference
Preterm	33 553	6.93	12 091	36.04	17.54 (17.06 to 18.04)
Multiple	13 399	2.77	3008	22.45	1.14 (1.08 to 1.19)

*Adjusted for maternal age, parity, infant sex, preterm and multiple birth. One hundred and fifty-eight and 63 records were missing maternal age and infant sex, respectively.

E-NAOI, English-version neonatal adverse outcome indicator.