Point-of-Care Ultrasound for Diagnosing Abdominal Pain in the Emergency Department

The goal of this clinical trial is to learn if adding an abdominal ultrasound scan to the standard examination helps emergency physicians make a correct diagnosis in adults with acute abdominal pain in the emergency department. The main question it aims to answer is: Does adding an abdominal point of care ultrasound scan to the standard examination increase the number of patients with acute abdominal pain in the emergency department, who get a correct preliminary diagnosis? Researchers will compare patients examined with an abdominal point-of-care ultrasound scan in addition to the standard examination to patients examined with the standard examination alone, to see if adding ultrasound improves diagnostic accuracy. Participants will: * Be randomly assigned to also have an abdominal point-of-care ultrasound scan performed by their doctor, or not * Have their doctor record a preliminary diagnosis and differential diagnosis * Have their medical records reviewed by an independent panel 30 days after their visit, to determine their final diagnosis

Inclusion Criteria: 1. ED contact. 2. Age ≥18 years. 3. Non-traumatic, acute abdominal pain, defined as symptom onset ≤7 days prior to presentation, as chief complaint. 4. Ability to provide written informed consent, as judged by the enrolling physician, and to communicate in Danish or English. Exclusion Criteria: 1. Prior enrollment in the trial. 2. Patients in whom the cause of the current abdominal pain is considered known at the time of enrolment (previously diagnosed condition explaining the current symptoms, e.g. known symptomatic gallstone disease). 3. Prior physician assessment of the presenting abdominal complaint during the current ED visit. 4. Prior ED assessment or received an abdominal ultrasound or CT scan for the same complaint, within the preceding 7 days. 5. Chronic abdominal pain, defined as abdominal pain persisting or recurring for ≥3 months(17), where the current episode represents an exacerbation of the chronic condition. 6. Patients requiring immediate critical care or rapid-response team activation.