RT Journal
A1 Cals JL, Metlay JP
T1 PRocalcitonin-based guidelines and lower respiratory tract infections
JF JAMA
JO JAMA
YR 2010
FD February 3
VO 303
IS 5
SP 418
OP 420
DO 10.1001/jama.2010.52
UL http://dx.doi.org/10.1001/jama.2010.52
AB 
In their discussion, the authors called for more widespread introduction of PCT measurement for milder LRTIs in outpatient physician offices. We think this conclusion is not justified because their study patients were managed in tertiary care settings. By focusing on the sickest patients with LRTI, the PCT test may have had better sensitivity in the study patients than it would have in less ill patients observed in primary care, a form of spectrum bias.