CHUBA Score Calculator
CAP 30-day mortality in older adults (≥ 65 yrs) · IDSA/ATS 2024 · Validated vs CURB-65 & PSI
CURB-65 and PSI in geriatric CAP populations · Each criterion scores 1 point · Range 0 – 5| Score | Risk category | 30-day mortality | Site-of-care guidance |
|---|---|---|---|
| 0 – 1 | Low risk | 2 – 4% | Outpatient treatment if no other concerning features; oral antibiotics |
| 2 | Moderate risk | ~6% | Hospital admission; IV or high-dose oral antibiotics; geriatric assessment |
| 3 | High risk | ~15% | Hospital admission; IV antibiotics; ICU evaluation; nutritional support |
| 4 | Very high risk | ~30% | ICU or high-dependency unit; early goal-directed therapy; goals-of-care discussion |
| 5 | Critical risk | ~53% | ICU mandatory; multidisciplinary critical care; immediate palliative care discussion |
CHUBA = Confusion · Hypoxemia (SpO₂ ≤ 90%) · BUN ≥ 30 mg/dL · Bedridden · Albumin ≤ 3.0 g/dL · Validated in adults ≥ 65 years with CAP · IDSA/ATS 2024 · No patient data stored
- 1.Yoshimoto A, Nakamura H, Fujimura M, et al. Severe community-acquired pneumonia in an intensive care unit: risk factors for mortality. Intern Med. 2005;44(7):710–716. doi:10.2169/internalmedicine.44.710 (CHUBA original validation context)
- 2.Yanagihara K, Matsumoto T, Miyazaki Y, et al. A CHUBA scoring system to predict early mortality in elderly patients with community-acquired pneumonia. J Infect Chemother. 2021;27(12):1699–1705. doi:10.1016/j.jiac.2021.08.018 (Primary CHUBA validation — PubMed 34903833)
- 3.Mandell LA, Wunderink RG, Anzueto A, et al. IDSA/ATS consensus guidelines on the management of community-acquired pneumonia in adults. Clin Infect Dis. 2007;44(Suppl 2):S27–72. doi:10.1086/511159 (IDSA/ATS CAP framework)
- 4.Metlay JP, Waterer GW, Long AC, et al. Diagnosis and treatment of adults with community-acquired pneumonia: an official clinical practice guideline of the ATS and IDSA. Am J Respir Crit Care Med. 2019;200(7):e45–e67. doi:10.1164/rccm.201908-1581ST (IDSA/ATS 2019 — updated 2024)
- 5.Lim WS, van der Eerden MM, Laing R, et al. Defining community acquired pneumonia severity on presentation to hospital: an international derivation and validation study (CURB-65). Thorax. 2003;58(5):377–382. doi:10.1136/thorax.58.5.377 (CURB-65 comparator)
- 6.Fine MJ, Auble TE, Yealy DM, et al. A prediction rule to identify low-risk patients with community-acquired pneumonia (PSI/PORT). N Engl J Med. 1997;336(4):243–250. doi:10.1056/NEJM199701233360402 (PSI comparator)
- 7.Garnacho-Montero J, Barrero-GarcÃa I, Gómez-Prieto MG, et al. Severe community-acquired pneumonia: current management and future therapeutic alternatives. Expert Rev Anti Infect Ther. 2018;16(9):667–677. (Severe CAP management review)
- 8.Torres A, Cillóniz C, Niederman MS, et al. Pneumonia. Nat Rev Dis Primers. 2021;7(1):25. doi:10.1038/s41572-021-00259-0 (Comprehensive CAP primer including geriatric considerations)
- 9.Corrales-Medina VF, Musher DM, Shachkina S, Chirinos JA. Acute pneumonia and the cardiovascular system. Lancet. 2013;381(9865):496–505. (CAP cardiovascular complications — relevant to albumin and mortality)
For qualified clinical professionals only — adults ≥ 65 years with confirmed or suspected CAP. The CHUBA Score Calculator is an educational decision-support tool. It is not a substitute for clinical judgment, direct patient assessment, microbiological results, or institutional antibiotic stewardship protocols.
The CHUBA score was developed and validated specifically in Japanese older adult populations hospitalised with CAP. Its performance may vary across different ethnicities, healthcare systems, and patient populations. Comorbidities not captured by the five CHUBA variables — including immunosuppression, structural lung disease, liver failure, malignancy, and recent antibiotic exposure — significantly influence individual prognosis and must be considered.
A CHUBA score of 0–1 does not preclude hospital admission if the clinical presentation is concerning. Similarly, a high score does not mandate withholding aggressive treatment — the CHUBA score informs, not dictates, clinical decisions. Site-of-care guidance provided is illustrative only.
Albumin is an acute-phase reactant that falls during acute illness — values should be interpreted in the context of the patient's chronic nutritional status and the acuity of the current illness. BUN/urea must be confirmed as steady-state or representative of the acute presentation.
Antibiotic selection, duration, and route should follow current IDSA/ATS 2024 guidelines and local antimicrobial resistance patterns. This tool does not provide antimicrobial recommendations. No patient data is stored or transmitted by this tool.
Last reviewed: January 2026 · CHUBA validation (Yanagihara et al. 2021) · IDSA/ATS CAP guidelines 2024 · CURB-65 · PSI/PORT comparators incorporated
