Background:Large multicenter studies comparing outcomes between TURP and photoselective vaporization of the prostate (PVP) are sparse, with no studies having compared the influence of trainee involvement on these outcomes. Our objectives were to assess 30-day outcomes after TURP and PVP with respect to trainee involvement using an independent national surgical database.Methods: Using the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) data (2005-2011), 7893 men were identified who underwent TURP or PVP. Regression models were constructed to assess associations between surgical approach, risk-adjusted morbidity and individual complications. Relationships between operative approach, operative duration and duration of stay were also examined and subdivided based upon trainee level.Results:Of 7893 patients, 4950 (62.7%) underwent TURP and 2943 (37.3%) underwent PVP. TURP patients were older, more likely to have diabetes, cancer, history of steroid use and preoperative transfusion compared with PVP patients, who were more likely to have coronary artery disease or bleeding disorders. Risk-adjusted overall morbidity was similar; however, PVP was associated with less pneumonia (0.2% vs 0.5%, P<0.015), bleeding requiring transfusion (0.5% vs 1.8%, P<0.001) and return to the operating room (1.5% vs 2.2%, P<0.022). PVP patients also had shorter length of stay (0.8 vs 2.1 days, P<0.001). There were no significant differences in outcomes when a trainee was involved. Operative duration was similar for TURP and PVP when performed by an attending alone (52 vs 52 min, P<0.001), but was longer with trainee involvement, regardless of post-graduate year (PGY) level (P<0.001). Comparison of operative duration among trainee subgroups demonstrated longer operative times for the PGY 6-9 subgroup performing PVP when compared with other subgroups (P<0.003).Conclusions:Within ACS NSQIP hospitals, TURP and PVP demonstrated similar risk-adjusted overall morbidity. Despite longer operative times for TURP and PVP with trainee involvement, there were no significant differences in outcomes.