The purpose of this critical appraisal is to determine if there is a significant difference between procalcitonin (PCT) guided treatment on antibiotic use and standard therapy in elderly patients (age 65 and older) with a suspected bacterial respiratory infection. The PICO question explored in this paper is: for elderly patients with a suspected bacterial infection, what effect does the result of a PCT test have on the determination of antibiotic use and outcome compared to patients treated empirically with antibiotics
