The value of a negative result

Scientific journals are filled with papers describing medical advances. Some are breakthroughs, others are more incremental improvements. In rare instances, journals publish studies on interventions that do not move the needle, but learning about them provides important insights.

That is the case with a new study from UC Davis Health’s Center for Healthcare Policy and Research (CHPR). The study, published in JAMA Network Open, tested communication strategies to reduce low-value, lower back (lumbar) spinal imaging.

Lower back pain is the single leading cause of disability worldwide. An estimated 75-85% of Americans experience some form of back pain during their life. In most cases, the pain is temporary.

When patients are in pain and want fast results, they may lobby for imaging, putting their doctors in an awkward position. While clinicians want to help their patients, they may also recognize that imaging studies often do not produce useful insights. In some cases, imaging can even generate false positives that may lead to unnecessary procedures.

“We have a problem in the United States of providing low-value services that are expensive, offer little or no benefit and are utilized at high rates,” said the first author on the paper, Joshua Fenton. He is the vice chair of research in the Department of Family and Community Medicine and a faculty member at CHPR. “Spinal imaging for patients with low back pain is one of those services, and we wanted to work with primary care doctors to see if we could reduce its unnecessary use.”

Staging a patient visit

In the study, actors playing simulated patients with low back pain visited primary care physicians. The actors were trained to give the physicians feedback on counseling strategies that could help the doctors steer patients away from unnecessary imaging. The feedback included tools to build trust, convey empathy and suggest patients adopt a “watchful waiting” strategy.

“Communication interventions using actors in the role of patients have had success in other studies,” Fenton said. “While this intervention seemed to boost empathic communication, it unfortunately did not affect imaging rates in patients with low back pain.”

The study included 53 primary care physicians in 10 clinics in two Sacramento area health care systems, including UC Davis Health. Physicians in the intervention group received three, 20-minute simulated office visits over six months.

The study’s primary outcome was the number of lumbar spinal images, occurring within 90 days of a low back pain visit, with an 18-month follow-up. It found that the imaging rates between the two groups were quite close: 15.7% for the intervention group and 17.3% for the control.

The study also assessed secondary outcomes, such as empathy and eliciting patient perspectives. Researchers found that the clinicians in the intervention group showed more empathy and asked for patient input, a noteworthy positive result.

A beneficial negative

The research team has some hypotheses about why this particular intervention did not work. One explanation is that the physicians in this study may have already been quite skilled at avoiding imaging, even without the coaching. Compared to national averages, the rates in both the intervention and control groups were low.

It’s also quite possible that the sessions were not enough.

While nonsignificant results in science are not ideal, they can be quite useful. Finding that this intervention is ineffective may help researchers pursue other strategies to reduce spinal imaging.

“Alongside other evidence, we believe our study shows physician educational interventions are simply not going to reduce low-value imaging,” Fenton said. “We need to consider approaches that operate at higher levels in health systems.”  

Other authors included: Camille Cipri, Melissa Gosdin, Daniel Tancredi, Anthony Jerant, Carly Ann Robinson, Guibo Xing, Ilona Fridman, Gary Weinberg and Andrew Hudnut. The study was funded by the Agency for Healthcare Research and Quality.