Table 4. Multiple linear regression analysis of the associations among birth weight, co-morbidities, and PMA at the time of full oral feeding.

	PMA at the achievement of full oral feeding (weeks)
	β	95% CI	p
Birth weight (100 g)	−0.3	−0.5; −0.2	<0.0001
BPD (yes vs no)	2.0	0.2; 3.8	0.03
GI surgical diseases (yes vs no)	3.6	1.6; 5.6	0.001
PDA (yes vs no)	−0.5	−1.8; 0.8	0.44
Sepsis (yes vs no)	0.6	−0.7; 2.1	0.30
Neurosensory diseases (yes vs no)	3.1	0.2; 3.8	0.06

PMA: postmenstrual age; CI: confidence interval; BPD: bronchopulmonary dysplasia; GI: gastrointestinal; PDA: patent ductus arteriosus.