Table 2.

Pearson intercorrelations of perinatal/neonatal characteristics for the ELGA and VLGA preterm infants combined (N=87)

	Gestational age at birth	Birth weight	Illness severity day 1	Mechanical ventilation (days)	Oxygen (days)	Pain exposure (number of skin breaking procedures)
Birth weight	0.79**
Illness severity day 1 (SNAP-II)	—0.52**	–0.39**
Mechanical ventilation (days)	—0.76**	–0.61**	0.43**
Other respiratory support (days)	—0.48**	–0.33**	0.25*	0.15
Pain exposure (number of skin breaking procedures)	—0.77**	–0.64**	0.58**	0.80**	0.38**
Morphine exposure (daily average mg/kg X days)	—0.55**	–0.45**	0.39**	0.68**	0.06	0.65**

^**P < 0.01

^*P < 0.05