Purpose: To determine whether "chronometric pressure" (i.e., a verbal prompt to increase speed) could predictably alter medical learners' speed-accuracy trade-off during a simulated surgical task, thus modifying the challenge.
Method: The authors performed a single-task, interrupted time-series study, enrolling surgery residents and medical students from two institutions in September and October 2015. Participants completed 10 repetitions of a simulated blood vessel ligation (placement of two ligatures 1 cm apart). Between repetitions 5 and 6, participants were verbally encouraged to complete the next repetition 20% faster than the previous one. Outcomes included time and accuracy (ligature tightness, placement distance). Data were analyzed using random-coefficients spline models.
Results: The authors analyzed data from 78 participants (25 medical students, 16 first-year residents, 37 senior [second-year or higher] residents). Overall, time decreased from the 1st (mean [standard deviation] 39.8 seconds [18.4]) to the 10th (29.6 [12.5]) repetition. The spline model showed a decrease in time between repetitions 5 and 6 of 8.6 seconds (95% confidence interval: -11.1, -6.1). The faster time corresponded with declines in ligature tightness (unadjusted difference -19%; decrease in odds 0.86 [0.76, 0.98]) and placement accuracy (unadjusted difference -5%; decrease in odds 0.86 [0.75, 0.99]). Significant differences in the speed-accuracy trade-off were seen by training level, with senior residents demonstrating the greatest decline in accuracy as speed increased.
Conclusions: Chronometric pressure influenced the speed-accuracy trade-off and modified the challenge level in a simulated surgical task. It may help unmask correctable deficiencies or false plateaus in learners' skill development.