What is the Fine Score (PSI)?
The Fine Score, also called the Pneumonia Severity Index (PSI), is a validated clinical prediction tool used to estimate mortality risk in adults with community-acquired pneumonia. It helps clinicians decide whether outpatient treatment, observation, or inpatient admission is most appropriate.
It combines demographics, comorbid conditions, physical findings, and selected laboratory/radiology variables into a weighted point total. Patients are then assigned to risk classes I through V.
How this calculator works
Step 1: Identify very low-risk Class I patients
In the original Fine approach, some patients can be assigned directly to Class I if they are younger, clinically stable, and free of high-risk comorbidities. This calculator checks those criteria first:
- Age under 50
- Not a nursing home resident
- No neoplastic disease, liver disease, CHF, cerebrovascular disease, or renal disease
- No altered mental status
- Pulse < 125, respiratory rate < 30, systolic BP ≥ 90, temperature 35 to < 40°C
Step 2: Compute PSI points
If Class I criteria are not met, points are summed. Age contributes a baseline score (age in years for men; age minus 10 for women), then additional points are added for each abnormal feature.
Interpretation of PSI risk class
- Class I: Very low risk (about 0.1% mortality), usually outpatient management if clinically appropriate
- Class II (≤70 points): Low risk (about 0.6%), often outpatient treatment
- Class III (71–90 points): Moderate risk (about 0.9–2.8%), brief observation or short admission may be appropriate
- Class IV (91–130 points): High risk (about 8–9%), inpatient treatment usually indicated
- Class V (>130 points): Very high risk (about 27–31%), inpatient care with possible ICU-level support
Clinical use and practical tips
When the PSI is especially helpful
- Emergency department disposition planning
- Standardizing triage across providers
- Communicating risk with patients and families
What PSI does not replace
The PSI should be integrated with bedside judgment, oxygen requirements, sepsis status, social factors, oral intake, and follow-up reliability. A patient with a low PSI score may still need admission for clinical reasons (for example, hypoxia requiring ongoing oxygen support or inability to safely manage at home).
Frequently asked questions
Is this the same as CURB-65?
Not exactly. CURB-65 is simpler and faster but uses fewer variables. PSI/Fine score is more detailed and often identifies low-risk patients with more granularity.
Can I use this for hospital-acquired pneumonia?
No. The Fine score was developed for adults with community-acquired pneumonia and may not perform the same in other contexts.
What if I do not have all lab values yet?
You can still calculate an interim score using available data. Missing optional labs in this calculator are treated as zero additional points; recalculate once full data is available.
Reference note
Scoring logic is based on the original Pneumonia Severity Index framework described by Fine and colleagues and commonly reproduced in internal medicine and emergency medicine references.