CALCA and ventilator-associated pneumonia: In 2005, a prospective study evaluated 63 patients and measured PCT on days 1, 3and 7 of follow-up to assess PCT kinetics during VAP.(42) A cutoff value of 1ng/mL on day 1 had asensitivity of 83% and a specificity of 64% in predicting the occurrence of anunfavorable outcome (28-day mortality, VAP recurrence, or extrapulmonaryinfection).