RT Journal
A1 DeCamp L, Dempsey AF, Tarini BA
T1 UNiversal primer polymerase chain reaction looks promising for newborns with low pretest probability of sepsis—reply
JF Archives of Pediatrics & Adolescent Medicine
JO Archives of Pediatrics & Adolescent Medicine
YR 2009
FD July 6
VO 163
IS 7
SP 675
OP 676
DO 10.1001/archpediatrics.2009.122
UL http://dx.doi.org/10.1001/archpediatrics.2009.122
AB 
Using test characteristics from Dutta et al,2 Drs Newman and Kohn demonstrate how a negative universal PCR result in an asymptomatic full-term infant translates into a posttest sepsis risk of 1 in 2500. They conclude that such a low risk of sepsis could change treatment in these newborns from empirical antibiotic therapy while awaiting blood culture results to observation without antibiotics. Their conclusion is based on the principle that “whether the result of a test should affect management decisions depends not on the sensitivity or specificity of the test, but on the posttest probability, which in turn depends on the pretest probability.” We agree wholeheartedly with Drs Newman and Kohn with respect to the fundamental importance of pretest probability when assessing the utility of diagnostic tests.