Outcomes of surgery among the Medicare aged: surgical volume and mortality.

We examined the relation between surgical volume and mortality, within 60 days of surgery, for eight procedures on aged Medicare beneficiaries. Logistic regression revealed that high surgical volume was significantly associated with lower mortality for resection of the intestine, coronary artery bypass, transurethral resection of the prostate (TURP), and hip arthroplasty (excluding total hip replacement). For cholecystectomy, total hip replacement, inguinal hernia repair, and femur fracture reduction, no relationship was found between surgical volume and postsurgical mortality. The analyses were repeated using inhospital deaths as the dependent variable, and the results indicated a considerably stronger association between volume and mortality.