• Anatomy Covers the structural knowledge essential for emergency procedures — including airway anatomy, vascular access sites, thoracic and abdominal organs, and musculoskeletal landmarks relevant to trauma and intervention.
• Physiology Tests understanding of how body systems function under normal and stressed conditions, including cardiovascular, respiratory, renal, and neurological physiology — critical for managing acutely unwell patients.
• Pharmacology Focuses on drugs commonly used in the Emergency Department — mechanisms of action, dosing principles, drug interactions, and toxicology — including anaesthetic agents, analgesics, and resuscitation medications.
• Pathology Assesses knowledge of disease processes at a cellular and systemic level, helping candidates understand the underlying mechanisms behind conditions they will encounter in the ED.
• Microbiology Covers relevant infectious organisms, their modes of transmission, and the principles of antimicrobial therapy, particularly in the context of sepsis and common emergency infections.
• Evidence-Based Medicine (EBM) & Statistics Tests the ability to critically interpret clinical research, understand study designs, and apply statistical concepts — an increasingly important skill for modern clinical practice.

In summary, the Primary is a science-heavy, foundation-level paper designed to ensure candidates have the core theoretical knowledge needed before progressing to the clinical stages of the MRCEM.