PSI / PORT Score

Fine MJ, Auble TE, Yealy DM, et al. A prediction rule to identify low-risk patients with community-acquired pneumonia. Derived and validated the Pneumonia Severity Index (PORT score): a two-step rule assigning Risk Classes I–V, with 30-day mortality 0.1–0.4% in Classes I–II and 27–31% in Class V.

The 2019 ATS/IDSA community-acquired pneumonia guideline recommends the PSI (over CURB-65) as the preferred severity tool to support the decision on outpatient versus inpatient treatment, together with clinical judgement.