Supervising Physicians' Prescribing Biases Reflected in Residents' Habits

A new study raises questions about whether the rhetoric of cost-effective care is being applied to real-world clinical training.

Resident physicians are twice as likely to order an expensive, brand-name statin when they're supervised by attending physicians who prefer those medications in their own practice.

That's the somewhat unsurprising finding of a study by researchers at Perelman School of Medicine at the University of Pennsylvania and published online in theJournal of General Internal Medicine.

"I wasn't at all surprised by the study," says Deborah Vozzella Hall, MD, national president of the American Medical Student Association (AMSA). "We are obviously influenced by what our teachers think. That's part of the nature of a teacher and student relationship."

But the study does raise questions about whether the rhetoric of cost-effective care is being applied to real-world clinical training.

"I don't think it is surprising that the most junior residents were prescribing like their supervising physicians. As an educator, I would expect residents to adopt their attendings' practice style," says Kira Ryskina, MD, a general internal medicine fellow at Penn and the study's lead author, responding to questions by email. "However, it was surprising to find that many attendings' prescribing was not aligned with cost-effective practices suggested by the "Top 5" list."

She's referring to the National Physicians Alliance's "Promoting Good Stewardship in Medicine" project, which produced lists of top 5 practices for high-value care. On the list for internal medicine was "use only generic statins when initiating lipid-lowering therapy."  Ryskina pointed out that these "'Top 5' lists gave rise to the Choosing Wisely Campaign by the ABIM Foundation and others."

Generic vs. Brand Name
"We wanted to determine whether residents… base their prescribing preferences between generic and brand name drugs based on the preferences of their supervising physicians," she said.

The researchers' sample included 342 residents and 58 attendings who wrote 10,151 initial statin prescriptions; among those, 3,942 were written by residents. They found that the probability of a first-year resident prescribing a brand-name statin was 22.6% when they were supervised by attending physicians who prescribed less than 20% brand-name statins.

The probability rose to 41.6% when the first-year resident was supervised by an attending who prescribed at least 80% brand-name statins.

The same effect wasn't seen for second- or third-year residents, though.

"We found that the most junior residents were heavily influenced by the prescribing preferences of their supervising attendings," Ryskina said. "However, we were surprised to find no relationship for more senior residents."

In fact, "A higher post-graduate year level was associated with brand-name prescribing," the study said.

"There are several possible explanations for this, such as attendings are not supervising senior residents closely enough in the area of cost-effective care, senior residents are not following attendings' recommendations, or that residents' styles are set early on in training," Ryskina said.

Hall, of AMSA, says that although cost-effective practices, including an emphasis on critical thinking and evidence-based medicine, is taught in the classroom, "how much that translates into what is emphasized in our clinical training is highly variable."

"I think, inherently, we want the approval of our teachers and we want to do well, and I think that can play a bigger role, particularly as an intern," she says. "You're still very closely supervised."

Moreover, it's the role of the attending physician to challenge residents' decision making and clinical choices. But if residents are getting challenged too often, and too harshly, perhaps they will simply bend to their supervisor's will and preference.

For example, a resident's thinking might go like this: "I will just prescribe what Dr. Jones prescribes because in the end, I have to answer to Dr. Jones," Hall says.

She also points out that physicians can be heavily influenced by the pharmaceutical industry. Certainly this influence can bleed into student training, and even starts in medical school: medical school and teaching hospital scorecards to grade schools' policies and relationships with the industry (although it should be noted that the Harvard study found no correlation between the strength of a school's policy regarding industry interactions and whether students accepted gifts). 

For instance, Perelman School of Medicine gets a "B" score (as of 2014), with "model policies" on preventing "faculty from being paid by industry to do promotional speaking, or to be on industry-funded speakers' bureaus" and not allowing industry-funded gifts of any nature or value, but having no policy about the access of medical device representatives.

"We think that medical education should focus on teaching people how to make evidence-based decisions," Hall says. "We should have strong conflict of interest policies in our programs, so we can make clinical decisions without undue external influence."

Certainly the new Penn study shows that there's still a wide gap between theory and practice, and between the classroom and the real-world, when it comes to providing low-cost care and following widely established recommendations.

"We hope this information will inform best practices to cultivate cost-effective care by physicians in training, an area of increasing emphasis in graduate medical education," Ryskina says.