Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Critical Care giúp cho các bạn có thêm kiến thức về ngành y học đề tài: Does serum procalcitonin have a diagnostic value in febrile adult patients presenting to the emergency department? | Available online http content 11 6 422 Letter Does serum procalcitonin have a diagnostic value in febrile adult patients presenting to the emergency department Jos AH van Oers1 Jaap E Tulleken2 and Jan G Zijlstra2 1 Department of Intensive Care St Elisabeth Hospital Tilburg The Netherlands 2Department of Intensive and Respiratory Care University Medical Center Groningen The Netherlands Corresponding author Jos AH van Oers E-mail jahvanoers@ Published 14 November 2007 This article is online at http content 11 6 422 2007 BioMed Central Ltd Critical Care 2007 11 422 doi cc6172 See related research by Hausfater et al. http content 11 5 R60 Hausfater and colleagues stated that in febrile adult patients presenting to the emergency department ED a proealeitonin PCT mcg l can help physicians to identify bacterial parasitic infections 1 . We disagree and want to illustrate that by calculating likelihood ratios LR . A LR is a semi-quantitative measure of the performance of a diagnostic test expressing the magnitude by which the pre-test probability of a diagnosis in a given patient is modified by the results of a test 2 . A positive result with a high positive likelihood ratio LR can rule in a diagnosis. A negative result with a low negative likelihood ratio LR- can rule out a diagnosis. LR for the emergency physician LR- . Using prevalence of bacterial parasitic infections as pre-test probability a positive diagnosis by the physician modified pre-test probability from 69 to 82 and a negative diagnosis to 37 . PCT mcg l LR and LR- . Pre-test probability changed to 81 by PCT mcg l and to 47 by PCT mcg l. The performance of the emergency physician is based on anamnesis physical examination and traditional markers such as neutrophil leukocytes and C-reactive protein CRP . For example CRP 40 mg l LR LR- . Pre-test probability changed by CRP 40 mg l to 82 and to 47 by CRP 40. Will the .
