Clinical reasoning, bias, and diagnostic uncertainty — KFP-style written assessment

KFP 1 (10 marks)

A 55-year-old man presents to the out-of-hours service with chest pain. The triage nurse has documented "musculoskeletal pain — likely strain from gardening". On your assessment the pain is central, does not vary with position, and he looks pale and sweaty. ^[4]

1. What cognitive biases are operating in this scenario? (4) ^{[1] [4]}
2. What should you do? (4) ^[1]
3. How does premature closure explain what nearly happened? (2) ^[4]

Model answers

1. Diagnostic momentum (the triage nurse's label of musculoskeletal pain is anchoring the team's thinking) and anchoring bias (fixating on the initial impression without reassessing). The pale, sweaty appearance contradicts the musculoskeletal label. ^{[1] [4]}
2. Treat this as possible ACS: ECG, aspirin 300 mg, urgent referral to hospital. Do not accept the triage label — re-examine and re-formulate independently. The presence of diaphoresis and pallor with central chest pain mandates cardiac assessment. ^[1]
3. Premature closure means accepting the musculoskeletal label without verification. Experimental evidence shows that early biasing information reduces diagnostic accuracy by 61% — the triage label was presented first and anchored the team's thinking. ^[4]