Laparotomy versus peritoneal drainage for necrotizing enterocolitis or isolated intestinal perforation in extremely low birth weight infants: outcomes through 18 months adjusted age. - Blakely ML; Tyson JE; Lally KP; McDonald S; Stoll BJ; Stevenson DK; Poole WK; Jobe AH; Wright LL; Higgins RD; NICHD Neonatal Research Network (Pediatrics, 2006)