The number of surgeries a hospital or surgeon performs is easily measured and has been used to denote clinical expertise. Procedure volume (number of cases per surgeon) has therefore become a widely-used quality indicator for surgery.
According to the Agency for Healthcare Research and Quality (AHRQ), a higher volume of carotid endarterectomy cases is associated with lower mortality and complication rates. Lower-volume facilities with well-trained surgeons may also achieve excellent clinical outcomes; however, the odds favor patients who are treated in hospitals where a higher number of procedures are performed.
A study of data analysis in one state reviewed hospital volume of CEAs and other procedures over a 10 year period. Researchers found that having a total hospital volume of more than 130 CEAs per year resulted in a statistically significant decrease in the chance of death (Southern Association for Vascular Surgery, 2008,)
Some hospitals care for patients with a greater severity of illness and their outcomes may reflect the increased surgical risk of those patients, e.g., sicker patients may increase the likelihood of poor outcomes.