Table 4 Multivariate analysis for readmission.

	AOR	95% CI
Infant sex
Male	1.93	1.10 to 3.41
Female (ref)
Gestational age
30–31 weeks	0.78	0.35 to 1.75
32–33 weeks	0.68	0.35 to 1.35
34 weeks (ref)
Bronchopulmonary dysplasia
Yes	2.95	0.82 to 10.56
No (ref)
Birth weight
<2000 g	1.09	0.56 to 2.12
⩾2000 g (ref)
Race/ethnicity
African‐American	1.49	0.62 to 3.55
White (ref)
Other	0.93	0.48 to 1.81
Combined hospital adverse outcome
Yes	1.53	0.65 to 3.59
No (ref)

Method used was logistic regression, with the dichotomous outcome of interest being any readmission during the three months after discharge from the birth stay. Of the 1250 infants in the cohort, 141 (11.3%) were admitted within three months of discharge. The model controls for clustering due to multiple births to the same mother. The adjusted odds ration (AOR) and 95% confidence interval (CI) were estimated from the logistic regression coefficients. Combined hospital adverse outcome is the occurrence of at least one of the following during the birth stay: pneumothorax, prolonged length of stay (discharge at >38 weeks postmenstrual age), sepsis/meningitis, or necrotising enterocolitis.