The benefit of these models is, however, mitigated by the observation that only one untreated pneumococcus infection would have been correctly classified as SBI by the best models, and a few “untreated SBI reclassified as SBI” (2/8 for NGAL/MxA/TRAIL, 1/9 for 5CV/MxA/TRAIL) were salmonella infections in older (2 and 3 years of age) children, for which no antibiotics therapy would have been recommended at our PED. Here, MX1 is linked to Salmonella Infections.