OBJECTIVE To evaluate the association of capsular dye and/or a pupil expansion device (PED) usage on the rate of major complication in resident-performed cataract extraction. METHODS Resident cataract surgeries between 2016 and 2019 were included. The primary outcomes were anterior or posterior vitrectomy (AVx and PPVx). Cases were grouped by the use of a PED and/or capsular staining along with additional preoperative risk factors. RESULTS Of the 1,348 cases, 371 (27.5%) documented capsular staining ("Dye-only"), 91 (6.8%) required pupil expansion ("PED-only"), and 100 (7.4%) used both capsular stain and a PED ("Both"). The remainder of cases (n=786, 58.3%) were classified as "Routine." Compared to the "Routine" group, "PED-only" and "Both" had significantly higher odds of an AVx (OR=2.90, 95% CI 1.27-6.19, P=0.01) and/or a PPVx (OR=2.33, 95% CI 1.07-5.12, P=0.04). Among the PPVx cases, the "PED-only" group has significantly higher odds than "Routine" and "Dye-only" (OR=4.64, 95% CI 1.68-12.79, P=0.01; and OR=6.48, 95% CI 1.7-25.0, P=0.005, respectively). In case-control analysis, vision, intraocular pressure, anterior chamber depth, axial length, cataract type, or severity had no significant overall association with complication. When compared to nuclear sclerotic cataract, posterior subcapsular (OR=7.86, 95% CI 1.46-42.47, P=0.017) and white/mature cataracts (OR=3.05, 95% CI 1.1-8.43, P=0.032) had increased odds of complication. CONCLUSIONS Resident-performed cataract surgery frequently required capsular staining and/or a PED, and intuitively, these cases had a higher overall complication rate compared to routine cases. However, the use of a PED independently was associated with significantly higher odds of a major complication requiring an unplanned vitrectomy independent of predisposing factors.