Evaluation of the SMS-ICU score for multicontinental use: A federated external validation study using critical care registry data
Objective To evaluate the suitability of the Simplified Mortality Score for the Intensive Care Unit (SMS-ICU) for use in critical care registries across multiple continents. Design A federated external validation study. Setting Intensive care units (ICUs) belonging to 12 critical care registries on five continents. Participants Individuals over the age of 18 years who were admitted to participating ICUs during the 2023 calendar year. Readmissions within the same hospital encounter and interhospital transfers were excluded. Interventions None. Main outcome measures The primary outcome was all-cause in-hospital mortality. A secondary analysis considered ICU mortality. Results 12 registries participated (three from Africa, four from Asia, one from Oceania, two from Europe and two from South America). In total, 494,705 admissions were included from 546 ICUs in 13 countries. Seven registries systematically reported hospital outcomes and were included in the primary analysis. Discrimination was acceptable (pooled area under the receiver operating characteristic curve [AUROC] 0.76 [95% CI 0.72–0.80]). Calibration and overall model fit varied between registries (Brier scores 0.09–0.14). In the secondary analysis of ICU outcomes in all 12 registries, discrimination remained acceptable but with higher variation between registries (pooled AUROC 0.73 [0.69–0.77]). Calibration and overall model fit also varied widely (Brier scores 0.07–0.46). Conclusions SMS-ICU may be used as an index of illness severity in international intensive care populations. This may facilitate international collaborative research and synthesis of findings in systematic reviews and meta-analyses.
Authors
- Otavio Ranzani
- Fathima Fazla (ORCID: https://orcid.org/0009-0000-6554-3899)
- Rashan Haniffa (ORCID: https://orcid.org/0000-0002-8288-449X)
- Alexander Tracy (ORCID: https://orcid.org/0000-0003-4109-3568)
- Bharath Kumar Tirupakuzhi Vijayaraghavan (ORCID: https://orcid.org/0000-0002-1801-0667)
- Tahlia Perumal (ORCID: https://orcid.org/0000-0003-0679-5804)
- Diptesh Aryal (ORCID: https://orcid.org/0000-0002-1431-8293)
- Giovanni Tricella (ORCID: https://orcid.org/0000-0002-0182-0364)
- Matti Reinikainen (ORCID: https://orcid.org/0000-0003-2501-2908)
- Menbeu Sultan
- Abigail Beane
- Ville Ihalainen
- Zakary Doherty
- Rabiul Alam Md Erfan Uddin
- Sylvia Brinkman
- Gastón Burghi
- Stefano Finazzi
- Jorge I.F Salluh
- David Pilcher
- Luigi Pisani
- David Thomson
- Moses Siaw-Frimpong
- Mohammed Basri Mat-Nor
- Dave Dongelmans
Institutions
- South African Medical Research Council (ZA)
- University of Cape Town (ZA)
- University of Eastern Finland (FI)
- Mario Negri Institute for Pharmacological Research (IT)
- Chittagong Medical College (BD)
- Komfo Anokye Teaching Hospital (GH)
- Hospital de Sant Pau (ES)
- Intensive Care Foundation (AU)
- Groote Schuur Hospital (ZA)
- Hospital Maciel (UY)
- International Islamic University Malaysia (MY)
- National Hospital of Sri Lanka (LK)
- Australian and New Zealand Intensive Care Society (AU)
- Kuopio University Hospital (FI)
- D’Or Institute for Research and Education (BR)
- South African Tuberculosis Vaccine Initiative (ZA)
- Mahidol Oxford Tropical Medicine Research Unit (TH)
- Apollo Hospitals (IN)
- Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (BR)
- Centre for Inflammation Research (GB)
- Amsterdam University Medical Centers (NL)
- St. Paul's Hospital Millennium Medical College (ET)
- Alfred Health (AU)
- University of Bari Aldo Moro (IT)
- Monash University (AU)
- University of Amsterdam (NL)
- University of Edinburgh (GB)
Publication Details
- Journal
- Critical Care and Resuscitation
- Published
- 2026-08-13
- DOI
- https://doi.org/10.1016/j.ccrj.2026.100206
- Primary Topic
- Sepsis Diagnosis and Treatment
- Type
- article
- Field-Weighted Citation Impact
- 0.00