Procedure volume as a quality measure for total joint replacement.

The association between procedure volume and post-procedure outcomes such as mortality or perioperative complications has been studied since the 1970s for a wide variety of procedures. A clear understanding of the implications of procedure volume for healthcare policy is critical because payers in both the private and public sectors have begun to develop policies that incorporate procedural volume data. In this review, we ask if procedure volume is a good surrogate measure of the quality of care. We focus specifically on literature related to total joint replacement. We have examined procedure volume as a quality measure with respect to four criteria -- validity, reliability, accessibility and capacity to enact policy. The strength of procedure volume as a quality indicator in total joint replacement (and numerous other procedures) lies in its ease of access and the strength and consistency of its association with numerous important health outcomes. These include mortality, dislocation, infection, revision rates, length of stay, medical complications and improved patient satisfaction. Although the current outcomes of total joint replacement are generally excellent, the large number of procedures performed annually makes even small improvements important. There is little information on the reliability of procedure volume assessments over time. The major weakness of procedure volume as a quality measure lies in its limited capacity to suggest cogent policy decisions. For total joint replacement, studies have failed to identify the processes that mediate the effect of increased procedure volume on patient outcomes. Consequently, there are few options for improving procedure volume beyond regionalization. More research is needed to identify the best method for regionalization and ensure that the access to health care of vulnerable populations is not compromised.