Regulating Trainee Workload in Laparoscopic Simulation: Evidence from NASA-TLX and Pupillometry Analysis.

OBJECTIVE

To explore whether a workload-adapted training protocol was associated with differences in trainee workload during laparoscopic simulation, using both self-reported and physiological measures. We hypothesized that adapting task difficulty to trainee progression would be associated with lower workload variability than a fixed-difficulty protocol.

DESIGN

A randomized, controlled experimental pilot study. Participants were randomized into an Experimental group (workload-adapted protocol: task difficulty increased from low to high) or a Control group (fixed-medium difficulty). Workload was assessed using NASA-Task Load Index (NASA-TLX) and real-time pupillary response (Tobii Pro Nano). Data were analyzed using mixed ANOVA, Levene's test for equality of variances, and Pearson correlation.

SETTING

Surgical Simulation Research Lab, University of Alberta, Edmonton, Alberta, Canada.

PARTICIPANTS

Twenty-two novice participants (university students) with no prior laparoscopic experience were recruited. All 22 participants completed the full training curriculum and subjective assessments; valid pupillary data were obtained from 16 participants.

RESULTS

NASA-TLX scores decreased significantly over time in both groups during training (p < 0.001). No significant between-group differences were observed in mean NASA-TLX scores or pupil size values (p > 0.05). However, the Control group showed significantly greater variance than the Experimental group for both NASA-TLX scores (p = 0.04) and pupil size (p = 0.03). These findings suggest that the workload-adapted protocol was associated with lower workload variability during training. A weak but statistically significant positive correlation was observed between NASA-TLX scores and pupil size (r = 0.19, p = 0.020).

CONCLUSIONS

These findings suggest that, within this pilot sample, the workload-adapted protocol was associated with lower workload variability during training. The observed association between pupillary response and NASA-TLX scores suggests that pupillometry may serve as a complementary physiological measure of trainee workload. These exploratory findings warrant validation in larger studies.