• Research

    Economies of scale: volume in health care

The concept is simple, if you perform the same procedure over and over; day in and day out, you tend to do it better, quicker, and safer than your counterpart who has only done it a few times, or infrequently. It’s referred to in other lines of work as “economies of scale.” The application of this concept dates back to Henry Ford and his novel use of this concept in the assembly line. However, unlike the assembly line with the ability to easily distinguish how many cars are generated, and the uniform safety of those cars and parts, health care still struggles to define these measures.

Researchers at the Mayo Clinic Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery, working with several clinical departments, have been finding that hospitals that perform the same procedure or treat the same condition repeatedly do it better than those who treat relatively few of the same condition or procedure. Increasing evidence also shows this relationship for some non-surgical therapies as well. There are better outcomes for patients, fewer complications, which translates into shorter length of stay, decreased mortality and increased survival just to name a few.

Under the direction of Sean Dowdy, M.D., a gynecologic surgeon and chair of the division of Gynecologic Surgery at Mayo Clinic, a team of researchers from Mayo Clinic’s Department of Obstetrics and Gynecology and the center studied this very issue. They published a paper in Obstetrics & Gynecology showing that despite clear guidelines to performing minimally invasive surgery for stage I-III endometrial cancer, this approach is only performed in a small portion of patients. Women are less likely to receive the accepted standard of care when performed at hospitals that treated the fewest of these patients.

Additionally, Ronald Go, M.D., a hematologist-oncologist published a paper in Cancer that showed non-Hodgkin lymphoma and a paper in the Journal of Clinical Oncology multiple myeloma patients treated at higher volume facilities may survive longer than those treated at lower volume facilities and have lower mortality, respectively.

Jeff Karnes, M.D., discussing options with a patient.

Another example of this is highlighted by the recent publication in Journal of Urology authored by Jeff Karnes, M.D., a urologic surgeon and chair of the Division of Community Urology, and other center researchers, describing the use of robots to assist in prostate cancer surgery.

The adoption of robotic-assisted radical prostatectomy (RARP) began in 2001, and gained rapid momentum as the technique of choice over the next decade, becoming the new gold standard by 2009. There is still debate around the efficacy of robot-assisted radical prostatectomy versus the pre-2009 gold standard of open radical prostatectomy. Because, while there is well-accepted evidence of the volume-outcome relationship of open radical prostatectomy, little evidence exists to show proficiency by volume results in better outcomes when conducting robot-assisted surgeries.

Dr. Karnes’ team found, “in 2011, 70% of hospitals averaged one RARP per week or less, accounting for 28% of RARPs. Compared to patients treated at the lowest quartile hospitals, those treated at the highest quartile hospitals had significantly lower rates of intraoperative complications, postoperative complications, perioperative blood transfusion, prolonged hospitalization, and mean total hospital costs.”

“Basically, we showed that larger volume hospitals and medical centers – where they are doing several a week or more – have better outcomes across this group of criteria,” says Dr. Karnes. “There is a clear dependency until a facility reaches about 100 RARPS a year, at which time further related improvement is minimal.”

“However, we also noted that a substantial proportion of RARPs are performed at low-volume hospitals,” Karnes says. “While further studies are necessary to identify additional determinants of perioperative outcomes and hospitalization costs, these results have important implications for health policy,” he states. “These types of findings seem to justify the centralization of major surgeries.”

This isn’t a new concept, but provides an ever growing body of evidence that should change thinking. The authors cite the fact that in 2002 in the United Kingdom, the National Health Services mandated radical prostatectomy be conducted only at centers that treated at least 50 such cases each year.

While the United States health care system may not be to this point, the work done by these teams is beginning to become a well-accepted fact of medicine and surgery; patients who go to a high volume center experience better outcomes. In an attempt to lower costs and make health care a free market, we must let informed patients make these crucial decisions about their care. Patients can arm themselves with this information when they are deciding on where to have a procedure. Policy makers and payers must heed this evidence and work to change the antiquated version of how we receive health care to allow patients to receive their care at these high volume centers.

Dr. Dowdy is also the Deputy Director of Practice within the Mayo Clinic Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery, where he works to effectively align the work of the CSHCD with the strategic priorities of the clinical practice at Mayo Clinic. Dr. Go has recently completed the Kern Health Care Delivery Scholars Program.

###