Physician Referral Rates Nearly Double in 10 Years

Jenni Laidman

January 23, 2012

January 23, 2012 — Physicians were nearly twice as likely to refer their patients to a specialist in 2009 as they were 10 years earlier, but the reason for the increase in referrals is unclear, according to an analysis of 2 national databases published in the January 23 issue of the Archives of Internal Medicine.

Michael L. Barnett, MD, from the Department of Health Care Policy, Harvard Medical School, and Division of General Internal Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, and colleagues analyzed a representative cross-section of ambulatory patient visits derived from the National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey.

They found an overall 94% increase in the probability a patient would be sent for referral (rising from 4.8% to 9.3%; P < .001) at a time when the overall number of physician visits was also rising. In 1999, there were 3040 physician visits for every 1000 people. Ten years later, there were 3720 office calls for every 1000 people. The number of visits resulting in referrals, in absolute numbers, rose 159%, from 41 million in 1999 to 105 million in 2009.

"This evolution in care patterns may be playing a role in the rising trajectory of health care spending in the United States because referrals to a specialist may lead to increased use of higher-cost services," the authors write.

However, the findings may uncover an even larger quandary. Mitchell H. Katz, MD, from the Los Angeles County Department of Health Services in California, writes in an accompanying editorial that "the real problem is that we have no idea what the data really mean."

It is not clear "whether we are currently referring too often, too infrequently, or (most likely) is unclear from the medical literature in general what the right frequency of referral is," Dr. Katz writes.

"There are no widely accepted guidelines for the referral of patients," he concludes.

Dr. Barnett and colleagues sound a similar note. "It is unclear whether the trends that we observed reflect a change in the appropriateness of referrals. This is the result, in part, of the fact that little guidance exists on how to optimally define the appropriate use of referrals. A recent review of the literature concluded that appropriateness of referrals has yet to be studied effectively."

Some of the biggest increases in referral rates were among physicians without an ownership stake in their medical practice, at 136% (going from 4.7% to 11.1%; P < .001). In contrast, the increase in referrals among physicians with a financial stake in their practice was less steep, at 79% over the course of 10 years (from 4.2% to 7.5%; P < .001), suggesting that financial incentives could influence referral patterns, the authors write.

Another potential cause of increasing referrals, the authors note, could be the growing complexity of care, "requiring ever more care by specialized physicians." The authors point to the referral practices of primary care physicians (PCPs), including family practice physicians, internists, and general practitioners, between the intervals of 1999 to 2002 and 2006 to 2009. Although referrals increased 71%, from 5.8% to 9.9% (P = .001), the pattern of referrals was telling, the authors suggest.

PCPs significantly altered the percentage of referrals for patients with cardiovascular symptoms (75%, from 8.5% to 14.9%; P = .001), dermatologic symptoms (52%, from 10.1% to 15.4%; P = .03), and ear, nose, and throat symptoms (89%, from 4.5% to 8.5%; P < .001). However, PCPs did not increase referrals as significantly "in areas that are more comfortably within the scope of primary care, such as general/viral symptoms," the authors write, which increased 41% (from 6.1% to 8.6%; P = .12).

Another hypothesis suggests that physicians under pressure for time refer more. The authors write that "physicians are increasingly faced with more to do during the typical visit despite no meaningful change in appointment duration in 2 decades."

More specialists in the market could also affect referral rates. The authors note that physicians practicing in outpatient departments had some of the highest referral rates in 1999, at 9.0%. Still, by 2009, their referral rates increased 84% to 16.6% (P < .001). Although their office-based peers saw an even steeper rise, at 95% (4.4% to 8.6%; P = .004), in referral rates, they still refer roughly half as often as outpatient department-based physicians.

The study also revealed that medical specialists dramatically increased referral rates (152%; from 2.9% to 7.3%; P < .001) and had higher referral rates for ear, nose, and throat complaints (95%; from 3.8% to 7.4%; P = .01), gastrointestinal complaints (179%; from 3.8% to 10.6%; P < .001), orthopedic complaints (91%; from 4.6% to 8.8%; P < .001), gynecological/breast symptoms (57%; from 3.7% to 5.8%; P = .04), and psychiatric complaints (85%; from 1.9% to 3.5%; P = .005).

In addition, PCP referral rates for gastrointestinal symptoms increased 44%, from 12.3% to 17.7% (P = .007), and referral for orthopedic symptoms increased 33%, from 12.4% to 16.5% (P = .003). There was no difference in referral rates between male and female patients, who were both referred in 9.3% of all visits in 2009.

Referral rates varied little by region, with the Midwest having the highest referral rate in 2009 (10%; P = .001), and the South having the lowest (8.9%; P = .02). One of the few groups for whom referral rates declined was uninsured patients, who saw referrals drop from 5.3% to 1.0% (P = .01), an 81% decrease, and the number of self-referrals also fell, from 6.0% to 2.8% of all visits (P < .001).

The study authors and Dr. Katz have disclosed no relevant financial relationships.

Arch Intern Med. 2012;172:163-170. Abstract


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.