Test characteristics of urinary SAA and platelet count.

*Cut-off line described by the linear function: [platelet count (109 cells/l)] –25 • [SAA (ng/ml)] <159.3. D = at diagnosis. D/S-1 = at diagnosis (D) of neonates with moderate NEC, who were operated on the same day or who died; pooled with levels at one day prior to surgery (S-1) in neonates who were operated after the day of diagnosis. LR+ = positive likelihood ratio. LR− = negative likelihood ratio. AUC = area under the curve. CI = Confidence interval.