Backgrounds: Despite efforts to evaluate plastic surgery residents’ operative performance, little is known regarding the time and cases needed for residents to achieve competency. We aim to use the Operative Entrustability Assessment (OEA), a validated 5-point scale, to assess the association between procedural difficulty and progression to competency.
Methods: OEA measurements were extracted from MileMarker™, a proprietary OEA-recording system. Surgical procedures were grouped by technical similarity; groups with ≥100 entries were included. Residents with <3 entries per group were excluded. Using clinical expertise, the senior authors assigned each surgery/surgical group a difficulty level from 1-5 (1=easy, 3=medium, 5=hard). “Competency” was defined as an OEA score ≥4. For each difficulty level, we calculated number of cases and time from first attempt to achieving competency. We used Kaplan-Meier methods to assess each difficulty level and multivariable Cox regression models to control for PGY level, resident gender, and training track.
Results: We included measurements for 222 residents and 6,249 OEAs. For difficulty levels 1-5, respectively, median number of cases logged to achieve competency were 3, 3, 4, 5, and 3; median times to competency were 6.1, 10.1, 12.1, 19.4, and 3.9 months. Kaplan-Meier analysis showed significant differences in time-to-competency between difficulty levels (p<.001). Residents achieved competency the fastest for level 1 and slowest for level 4 procedures. Progression to competency was similar in levels 2, 3, and 5. In the Cox regression analysis, hazard ratios (95% CI) for achieving competency for levels 2 to 5 (compared to level 1) were 0.51 (0.40-0.65), 0.53 (0.41-0.68), 0.38 (0.29-0.51), and 0.32 (0.22-0.46), respectively. Gender and training track were not associated with progression to competency.
Conclusion: Before adjusting for PGY level, residents appeared to require similar amounts of time to achieve competency in level 2, 3, and 5 procedures, likely demonstrating faculty are providing residents operative autonomy appropriately according to residents’ skill acquisition. However, adjusting for PGY level shows residents need significantly more time to achieve competency in increasingly difficult cases. Using difficulty levels to assign residents plastic surgery procedures may help faculty better parse out differences in progression among surgical trainees and accelerate operative skills acquisition.