We estimate that 60 colectomies for FCDC will be performed per year (at 20 institutions) (5). Neal et al. report an absolute risk reduction of 31% in 30 day mortality. However, given that this was a single surgeon experience and that our current 30-day mortality is 38% (5) (in contrast to 50% for TAC in Neal et al.'s series), we anticipate an absolute risk reduction of 22%. For this reduction, with a type I error rate of 0.05, a power of 80%, a 1:1 control to intervention ratio, 63 patients are required in each arm, and are estimated to be accrued over 2 years. We will also cluster by surgeon and institution, however as each surgeon and institution are only expected to contribute very few (approximately 1-3) cases, we are estimating a small intraclass correlation coefficient and design effect close to 1.