[2] This is consistent with the conclusions stated in the original report that published the PSI/PORT score:[1] "The prediction rule we describe accurately identifies the patients with community-acquired pneumonia who are at low risk for death and other adverse outcomes.
The purpose of the PSI is to classify the severity of a patient's pneumonia to determine the amount of resources to be allocated for care.
Most commonly, the PSI scoring system has been used to decide whether patients with pneumonia can be treated as outpatients or as (hospitalized) inpatients.
[6] In the 2019 ATS/IDSA Guidelines for the Diagnosis and Treatment of Adults with Community-acquired Pneumonia, PSI was recommended over CURB-65 because of lack of evidence supporting the safety and effectiveness of the latter.
One significant caveat to the data source was that patients who were discharged home or transferred from the MedisGroup hospitals could not be followed at the 30-day mark, and were therefore assumed to be "alive" at that time.