Kaukonen KM, et al. - Researchers examined the association of different Systemic Inflammatory Response Syndrome (SIRS) criteria with hospital mortality among patients with infection, organ failure, and at least one SIRS criterion in 179 Intensive Care Units in Australia and New Zealand. Different individual and combinations of SIRS criteria were shown to be related to marked variations in hospital mortality. It was noted that mortality increased from 10.6% for the respiratory rate criterion to 15.8% for the heart rate criterion; from 10.1% for the high leukocyte count criterion to 20.0% for a low count and from 10.1% for a high temperature to 14.4% for a low temperature criterion. A variation in hospital mortality from 11.5% to 30.8% was noted with any two SIRS criteria, depending on the combination of criteria. After adjustment and over time, no change was noted in these differences. It was implied that individual SIRS criteria are not equivalent or interchangeable.