This study aims to evaluate how well a new scoring system called the Sequential Organ Failure Assessment-2 (SOFA-2) works in adult intensive care units in Türkiye.

SOFA-2 is designed to measure the severity of organ dysfunction in critically ill patients using routinely collected clinical and laboratory data. It is an updated version of the original SOFA score and reflects modern intensive care practices.

In this multicenter observational study, adult patients admitted to participating intensive care units will be followed during their ICU stay. SOFA and SOFA-2 scores will be calculated during the first 24 hours of admission, and in patients with longer stays, additional scores will be recorded. No additional tests or treatments will be performed as part of the study.

The main goal of the study is to examine the relationship between SOFA-2 scores and intensive care unit mortality. The results are expected to help clinicians better assess disease severity and outcomes in critically ill patients.

This is a multicenter, prospective, observational study designed to evaluate the feasibility and prognostic performance of the Sequential Organ Failure Assessment-2 (SOFA-2) score in adult intensive care units across Türkiye.

Adult patients aged 18 years or older who are admitted to participating intensive care units and remain in the ICU for more than 24 hours will be eligible for inclusion. Pregnant patients, organ donors, patients younger than 18 years, and those with unknown ICU discharge outcomes will be excluded.

Demographic characteristics, reasons for ICU admission, comorbid conditions, and routinely collected clinical and laboratory data will be prospectively recorded using standardized case report forms. SOFA and SOFA-2 scores will be calculated based on data obtained during the first 24 hours following ICU admission. For patients with an ICU stay longer than 72 hours, additional SOFA and SOFA-2 scores will be recorded at 72 hours.

Patients will be followed until ICU discharge or death. No study-specific interventions, additional diagnostic procedures, or changes to standard clinical management will be implemented as part of the study.

The study will assess the feasibility of real-time SOFA-2 score calculation, evaluate its association with ICU mortality, and compare its prognostic performance with the original SOFA score. Analyses will account for the multicenter structure of the study and variations across participating intensive care units.

Inclusion Criteria:

• Adults aged 18 years or older
• Admission to a participating intensive care unit in Türkiye
• Intensive care unit stay longer than 24 hours

Exclusion Criteria:

• Patients younger than 18 years
• Pregnant patients
• Organ donors
• Patients with unknown intensive care unit discharge outcomes

The study population consists of adult patients admitted to participating intensive care units across Türkiye. Eligible participants are critically ill adults who require intensive care monitoring and treatment and remain in the intensive care unit for more than 24 hours. The study includes a broad and heterogeneous ICU population reflecting routine clinical practice and does not target a specific dise

De-identified individual participant data related to baseline demographics, ICU admission characteristics, SOFA and SOFA-2 scores, and ICU outcomes that underlie the results reported in the primary publication will be shared. No direct identifiers or protected health information will be included.

Beginning 6 months after publication Ending 5 years after publication

Supporting information and de-identified individual participant data will be made available upon reasonable request. Requests will be reviewed by the study steering committee, and access will be granted following approval of a methodologically sound proposal and execution of a data use agreement.