Understanding never events: developing an ecologically valid behavioral test for left-right confusion during surgery

The accurate distinction between left and right is a critical cognitive function. A failure to correctly distinguish left and right during surgery can lead to a so-called Never Event, a preventable medical error that leads to death or severe injury of the patient. Unfortunately, such wrong-site surgeries still happen every year. Thus, understanding left-right confusion during surgery is critical for patient safety. However, current Left-Right Confusion (LRC) tests have low ecological validity for the complex, time-critical demands of a surgical environment. This study introduces the Never Events in Surgery Test (NEST), a novel, ecologically valid behavioural paradigm designed to simulate the cognitive dynamics during surgery.

Participants (N = 108) completed the NEST alongside established LRC tasks: the Bergen Left-Right Discrimination Task (BLRDT), the Left-Right Commands Task (LRCT), and the Left-Right Questionnaire (LRQ).

NEST performance was significantly modulated by the posture of the training doll. Error rates were lowest in the prone position compared to lateral orientations (p < 0.05), while the supine position resulted in the shortest reaction times, significantly outperforming both prone and lateral positions (p < 0.001) without a significant increase in error rates. Crucially, the study established a cognitive dissociation: while reaction times across tasks were correlated, reflecting a shared component of general processing speed, the error rates from the established LRC measures (BLRDT, LRCT, LRQ) failed to predict the error rate observed in the applied NEST paradigm.

The lack of predictive power for errors suggests that LRC susceptibility in applied contexts is an independent, context-specific risk factor for laterality errors not captured by traditional assessments. The findings argue for a paradigm shift in training and screening toward tailored, context-specific approaches.