Journal Watch : Annals of Surgery, May 2009.

Surgical Specialization and Patient Outcome

There is great interest in the degree to which surgical specialization affects outcomes. (see Benefits Of Specialization). Prior discussions regarding positive volume-outcome relationships have debated whether "practice makes perfect" or whether better surgeons get more referrals and therefore have higher volumes. This raises two relevant questions. Does specialization itself lead to reduced mortality, or do better surgeons become specialists?

This issue is re-examined in a recent study and the accompanying editorial published in Annals of Surgery, May 2009. The authors in this study propose that either "better surgeons become specialists" or that "the specialist seems to be good at 'everything' they do." The authors postulate that those "surgeons who are 'good' to begin with, and thus will be good at everything they do, choose or are selected to be become specialists," and that the specialist seems good at everything they do.

The differences in outcomes between specialist and general surgeons may be explained in several ways, including the effect of high volume, systematic differences in choice of treatment and the contribution of other healthcare professionals. Specialist surgeons are more likely to perform higher volumes of select procedures. Four studies however that have examined the independent contributions of specialization and volume of surgery have demonstrated that when volume discrepancies between specialist and general surgeons were controlled for, the benefit from specialization was still apparent. These findings suggest that the benefit of specialization cannot be explained simply by 'practice makes perfect'. High surgeon volume and specialization are independently associated with improved patient outcome.

In a simplistic sense, the specialist appears good at "everything" they do: something important about being a specialist spills over into all their cases. Two possible contributing explanations, which are not exclusive, might be most significant: "Selection bias" versus "Acquired ability." Under the selection bias theory, surgeons who are "good" to begin with, or have the innate ability to be good, and thus who will be good at everything they do, choose or are selected to become specialists. Under the acquired ability theory, something about the process of specializing in certain procedures (the fund of knowledge or the learning processes that lead to a special fund of knowledge, the attention to detail in diagnosis/surgery/management, certain patient management processes or the attention to processes in general, the process of skills acquisition or the development of generalizable technical skills, etc) leads to generally better patient outcomes spilling across all cases.

The unintended consequences of the drive to specialization must however be carefully considered from a public health standpoint. This is why countries are faced with a serious projected shortage of general surgeons, surgeons able and willing to take emergency calls and surgeons able and willing to work in rural areas. What will be the ultimate impact from the move to specializations on public health?

Take home message for patients: The proposed underlying explanations are probably not of great relevance to the individual breast cancer patient; the fact is that overwhelming evidence supports the finding that outcomes are better for breast cancer patients treated by high volume specialist breast surgeons compared to those treated by lower volume general surgeons.