What is the association between CABG volume and unadjusted mortality rate?
The STS Adult Cardiac Surgery Database found a weak association between volume and unadjusted mortality rate, with a 2.6% unadjusted mortality rate for hospitals performing 100 procedures versus 1.7% for hospitals performing 450 procedures. However, this association was weaker when proper risk adjustment based on clinical data and hierarchical models were used that account for small sample sizes and clustering of observations.