Pneumonia Severity Index Calculator

About this calculator

The Pneumonia Severity Index (PSI), also known as the PORT score (Pneumonia Outcomes Research Team), is a clinical prediction rule that estimates a patient’s 30-day mortality risk from community-acquired pneumonia by combining age, sex, comorbidities, and vital signs — respiratory rate, blood pressure, temperature, heart rate, oxygen saturation, and mental status — into a single point score. The point total sorts patients into risk classes I through V, with higher classes indicating higher mortality risk and typically guiding the decision between outpatient treatment, brief observation, or hospital admission.

This simplified calculator reproduces the core structure of the PSI/PORT approach — combining age, sex, and key vital signs into an estimated score and risk class — as an educational approximation of the full clinical rule, which in practice also weighs comorbid conditions (cancer, liver disease, heart failure, cerebrovascular disease, renal disease) and additional lab and imaging findings. Emergency physicians and hospitalists use the full PSI/PORT score as one of several tools to triage pneumonia severity and decide site-of-care; this tool is for general understanding only and is not a substitute for clinical evaluation.