differential diagnosis approach that triages patients according to their presenting complaints and objective assessments such as vital signs and Glasgow Coma Scale, allowing acute patients to be identified quickly for treatment. PACS classifies patients into four main categories: P1, P2, P3, and P4. Spain In Spain, there are 2 models which are the most common found in hospitals around the country: The Sistema Estructurado de Triaje (SET), which is an adaptation of the Model Andorrà de Triatge (MAT). The system uses 650 reasons for medical appointment in 32 symptomatic categories, that together with some patient information and basic exploratory data, classifies the emergency within 5 levels of urgency. The "Manchester", based on the system with the same name in the UK, use 51 reasons for consultation. Through some yes/no questions, addressed in a diagram, it classifies the emergency in 5 severities. Some autonomous communities in Spain, like Navarre and the Valencian Community, have created their own systems for the community hospitals. United Kingdom In the UK, the commonly used triage system is the Smart Incident Command System, taught on the MIMMS (Major Incident Medical Management (and) Support) training program. The UK Armed Forces use this system on operations. This grades casualties from Priority 1 (needs immediate treatment) to Priority 3 (can wait for delayed treatment). There is an additional Priority 4 (expectant, likely to die even with treatment) but the use of this category requires senior medical authority. In the UK and Europe, the triage process used is sometimes similar to that of the United States (see below), but the categories are different: – patients who have a trauma score of 0 to 2 and are beyond help – patients who have a trauma score of 3 to 10 (RTS) and need immediate attention – patients who have a trauma score of 10 or 11 and can wait for a short time before transport to definitive medical attention – patients who have a trauma score of 12 (maximum score) and can be delayed before transport from the scene From April 2023, the NHS and ambulance services are to adopt the Major Incident Triage Tool, a new triage tool that will be used in mass causality incidents. This tool was a result of large multi-disciplinary review led by the NHS but its implementation became more urgent after the Manchester Arena Inquiry made it a monitored recommendation for the NHS and National