Acute pancreatitis is an important gastrointestinal emergency that may lead to mortality, particularly in older patients. This retrospective, single-center observational prognostic validation study aims to compare the predictive performance of the National Early Warning Score 2 (NEWS-2) and NEWS-Calcium scores for in-hospital mortality in patients aged 65 years and older diagnosed with acute pancreatitis in the emergency department.

Electronic medical records of eligible patients will be reviewed retrospectively. Demographic characteristics, vital signs, serum calcium levels, clinical outcomes, intensive care unit admission, organ failure, length of hospital stay, and in-hospital mortality will be recorded. NEWS-2 will be calculated using vital parameters at admission, while the NEWS-Calcium score will be obtained by adding a calcium-based score to NEWS-2.

The primary outcome will be in-hospital mortality. Secondary outcomes will include intensive care unit admission, severe acute pancreatitis, persistent organ failure, and length of hospital stay. The predictive performances of the scores will be compared using ROC curve analysis, AUC values, and the DeLong test. This study aims to identify the most appropriate early prognostic score for older patients with acute pancreatitis and to support clinical decision-making in emergency settings.

Acute pancreatitis is a common gastrointestinal emergency that may be associated with significant morbidity and mortality, particularly in older patients. In individuals aged 65 years and older, reduced physiological reserve, increased comorbidity burden, and delayed clinical deterioration may make early risk stratification more important in the emergency department.

The National Early Warning Score 2 (NEWS-2) is a widely used clinical scoring system based on routinely measured physiological parameters, including respiratory rate, oxygen saturation, systolic blood pressure, pulse rate, level of consciousness, temperature, and supplemental oxygen use. Calcium abnormalities, especially hypocalcemia, may also be associated with disease severity and poor outcomes in acute pancreatitis. Therefore, a calcium-integrated scoring approach may improve early prognostic assessment in this patient population.

This study is designed as a single-center, retrospective, observational prognostic validation study. The study will include patients aged 65 years and older who were admitted to the emergency department and diagnosed with acute pancreatitis during the predefined study period. Eligible patients will be identified through electronic medical records. Demographic characteristics, comorbidities, vital signs at emergency department admission, laboratory parameters including serum calcium levels, clinical outcomes, intensive care unit admission, organ failure status, length of hospital stay, and in-hospital mortality will be recorded.

The NEWS-2 score will be calculated using physiological parameters measured at the time of emergency department admission. The NEWS-Calcium score will be calculated by adding a calcium-based component to the NEWS-2 score according to serum total or corrected calcium levels. The primary outcome of the study will be in-hospital mortality. Secondary outcomes will include intensive care unit admission, development of severe acute pancreatitis, persistent organ failure, and length of hospital stay.

The main objective of this study is to compare the predictive performance of NEWS-2 and NEWS-Calcium scores for in-hospital mortality in older patients with acute pancreatitis. Receiver operating characteristic (ROC) curve analysis will be used to evaluate the prognostic performance of each score. The area under the curve (AUC), sensitivity, specificity, positive predictive value, negative predictive value, and optimal cut-off values will be calculated. The AUC values of NEWS-2 and NEWS-Calcium will be compared using the DeLong test.

This study is expected to provide evidence on whether the addition of serum calcium to NEWS-2 improves early mortality prediction in geriatric patients with acute pancreatitis. The findings may contribute to early risk stratification, clinical decision-making, and appropriate allocation of intensive care resources in the emergency department.

Inclusion Criteria:

• Age 65 years or older.
• Admission to the emergency department with a diagnosis of acute pancreatitis during the study period.
• Diagnosis of acute pancreatitis established according to clinical presentation, serum pancreatic enzyme levels, and/or imaging findings.
• Availability of admission vital parameters required to calculate the National Early Warning Score 2 (NEWS-2).
• Availability of serum calcium measurement at emergency department admission.
• Availability of in-hospital clinical outcome data.

Exclusion Criteria:

• Age younger than 65 years.
• Absence of a confirmed diagnosis of acute pancreatitis.
• Missing data required to calculate NEWS-2 or NEWS-Calcium scores.
• Missing serum calcium measurement at admission.
• Incomplete medical records or unavailable in-hospital outcome data.
• Transfer to another hospital before clinical outcome assessment.
• Recurrent admissions during the study period; only the first eligible admission will be analyzed.

The study population will consist of patients aged 65 years and older who were admitted to the emergency department and diagnosed with acute pancreatitis during the predefined study period. Eligible patients will be identified retrospectively through electronic medical records. Patients with available admission vital signs, serum calcium levels, and in-hospital outcome data will be included. Patients with missing data required for calculation of NEWS-2 or NEWS-Calcium scores, unavailable outcome data, or transfer before outcome assessment will be excluded. Only the first eligible admission will be analyzed for patients with recurrent admissions.

Individual participant data will not be shared. This is a retrospective study based on electronic medical records, and individual-level patient data will not be made available to other researchers due to confidentiality, ethical, and institutional data protection regulations. Only aggregated and anonymized study results will be reported.