Emergency physicians are required to identify life-threatening conditions in patients who presenting with vague or non-specific symptoms. Common complaints such as chest pain, dizziness, and back pain account for a large proportion of ED presentations. Hidden within these are the critical “1%” - patients with time-sensitive, high-risk diagnoses such as aortic dissection, posterior circulation stroke, and cauda equina syndrome.

These conditions are difficult to diagnose, frequently missed, and associated with significant morbidity, mortality, and medicolegal risk. This talk explores the diagnostic challenges posed by these conditions, highlighting common cognitive pitfalls and system-level contributors to diagnostic error. Practical strategies will be presented to improve diagnostic accuracy, mitigate risk and improve patient outcome.