Where did these darn numbers come from?

Today’s most difficult credentialing challenge is finding a way to meaningfully link physicians’ demonstrated competence with the privileges that the medical staff grants them. The Joint Commission’s standard MS.06.01.05 has raised the bar for this challenge by requiring that the decision to grant or deny a privilege and/or to renew an existing privilege is an objective, evidenced-based process. But just in case you thought conflicts over how to establish privileges are new, it pays to remember the words of Dr. Kenneth Babcock, former director of the then Joint Commission on Accreditation of Hospitals, when he said, “There is no more controversial question in medical practice than who may be granted hospital privileges and to what extent.” The year was 1962.

Much progress has been made since then in moving privileging in the direction of a more “objective, evidence-based process.” One step was formulating the challenge of privileging in what has come to be known as the “Competency Equation.” The Competency Equation states:

Competency = Evidence you did it recently + Evidence that when you did it, you did it well

If we can “solve” for both terms in this equation, we can establish current competence. But this is harder than it looks. The first question to answer is, “What do you mean by ‘it’?” In other words, how will we delineate the scope of activities for which we will be solving the Competency Equation? The way we do this now is through delineation of privileges. The “it” can be a single line on a laundry list or a cluster of clinical activities, similar to what medical staffs now call core privileging and competency clusters. For example, the “it” could be colon resection, or it could be a cluster of large bowel procedures, or a cluster of abdominal procedures, or the entire core for general surgery. However we define “it”, once we have established that a clinician did the “it” recently, we must then solve the second part of the equation. We must be able to answer the question, “Did the practitioner do ‘it’ well?” To answer this question we need to turn to the results of peer review.

This brings us to the moment when we must confront whether to use minimum threshold numbers as eligibility criteria. First of all, if you did not do at least one “it” recently, you can’t say anything meaningful about your current competence to perform “it.” (Physicians are fond of claiming that many procedures are like riding a bicycle, meaning competence is maintained over many years, even if the physician did not do any procedures recently. We will address this issue in a future edition of Medical Staff Leader Connection.)

Once we have established that you have done at least one ”it” recently, we must then ask the question, “How many must you have done recently for the medical staff to say something meaningful about your competence to do it?” If a provider did one procedure with good results, does this mean he or she is competent to do “it”? Not with much validity. How about if he or she did two procedures? If the physician completed the procedures without incident, the medical staff can say something just a little more meaningful than after only one procedure, but not much more than that. You can see how this line of logic can bring us to seek a number of “its” as a minimum criterion for eligibility to request a privilege. Common sense leads us to minimum volumes that will be in the range of five to 30 “its” depending on how broad the “it” is defined.

But common sense doesn’t strike most of us as adequately objective and evidence-based. The logical next step is to ask if there is any good research that links a minimum volume of procedures or conditions to outcomes for individual practitioners. Though there is some research on this subject, unfortunately the list of “its” for which we have good-evidence based research linking volume to competence is remarkably small—less than 15 procedures. Examples include esophagectomy and coronary artery bypass graft surgery, though the degree to which the outcomes are linked to the competence of the surgeon versus the competence of the entire team is not always clear. For the vast majority of the privileges granted to physicians, there is little or no good research that links outcomes to any minimum number of procedures performed or patients cared for.  In addition, minimum volume thresholds that may make sense in a busy, urban teaching hospital where most research is typically conducted may not be applicable to small or moderate communities.

Does this mean minimum threshold eligibility criteria for privileges should be dropped? Not if we are serious about solving the Competency Equation. Over time, more research will demonstrate the procedures or conditions for which volume correlates with outcomes, especially those for which a minimum volume can be identified that differentiates those with good enough outcomes from those with outcomes that fall below some threshold of acceptability. Until then, there is no straight forward answer to the typical question raised by physicians when confronted with threshold volumes for privilege eligibility—“Where did these darn numbers come from!?” The best answer is to ask those physicians, “What is the minimum number of procedures a provider needs to have done recently for us to meaningfully determine if the provider did them well?” This approach will take us a few more steps down the road toward making privileging an objective, evidence-based process, at least to the best of our ability today.

Richard A. Sheff, MD, CMSL, is a chair and executive director of The Greeley Company, a division of HCPro, Inc. in Marblehead, MA.