Provider Experience and the Comparative Safety of Laparoscopic and Open Colectomy.

<bold>Objective: </bold>To evaluate the comparative safety of laparoscopic and open colectomy across surgeons varying in experience with laparoscopy.<bold>Data Sources: </bold>National Medicare data (2008-2010) for beneficiaries undergoing laparoscopic or open colectomy.<bold>Study Design: </bold>Using instrumental variable methods to address selection bias, we evaluated outcomes of laparoscopic and open colectomy. Our instrument was the regional use of laparoscopy in the year prior to a patient's operation. We then evaluated outcomes stratified by surgeons' annual volume of laparoscopic colectomy.<bold>Principal Findings: </bold>Laparoscopic colectomy was associated with lower mortality (OR: 0.75, 95 percent CI: 0.70-0.78) and fewer complications than open surgery (OR: 0.82, 95 percent CI: 0.79-0.85). Increasing surgeon volume was associated with better outcomes for both procedures, but the relationship was stronger for laparoscopy. The comparative safety depended on surgeon volume. High-volume surgeons had 40 percent lower mortality (OR: 0.60, 95 percent CI: 0.55-0.65) and 30 percent fewer complications (OR: 0.70, 95 percent CI: 0.67-0.74) with laparoscopy. Conversely, low-volume surgeons had 7 percent higher mortality (OR: 1.07, 95 percent CI: 1.02-1.13) and 18 percent more complications (OR: 1.18, 95 percent CI: 1.12-1.24) with laparoscopy.<bold>Conclusions: </bold>This population-based study demonstrates that the comparative safety of laparoscopic and open colectomy is influenced by surgeon volume. Laparoscopic colectomy is only safer for patients whose surgeons have sufficient experience. [ABSTRACT FROM AUTHOR]