RAPID score = renal + age + purulence + infection-source + albumin points.

Domain	Category	Points
Renal	Urea <5.0 mmol/L or BUN <14 mg/dL	0
Renal	Urea 5.0–8.0 mmol/L or BUN 14–23 mg/dL	1
Renal	Urea >8.0 mmol/L or BUN >23 mg/dL	2
Age	<50 years	0
Age	50–70 years	1
Age	>70 years	2
Purulence	Purulent pleural fluid	0
Purulence	Non-purulent pleural infection	1
Infection source	Community-acquired	0
Infection source	Hospital-acquired	1
Albumin	≥27 g/L (≥2.7 g/dL)	0
Albumin	<27 g/L (<2.7 g/dL)	1

Total score range: 0–7. Risk bands are 0–2 low, 3–4 medium and 5–7 high.

RAPID Score for Pleural Infection