A University of Louisville physician and researcher has helped raise the profile of a leading medical journal to an all-time high.

The journal Circulation Research, edited by UofL’s Roberto Bolli, M.D., has achieved its highest-ever “impact factor,” a measure of its importance in the medical field. Circulation Research is an official journal of the American Heart Association and is considered the world’s leading journal on basic and translational research in cardiovascular medicine. Its impact factor, calculated yearly and just announced for 2016, places it among the top 2 percent of medical journals.

Bolli, chief of Cardiovascular Medicine at the UofL School of Medicine and UofL Physicians, took over as editor of the journal in 2009, and has worked to raise the journal’s profile since. He also serves as director of UofL’s Institute of Molecular Cardiology and scientific director of the Cardiovascular Innovation Institute.

The impact factor (IF) is a measure of the frequency with which the average article in a journal has been cited in other articles and medical literature in a particular year. The more cited a journal is, the more “impact” it has on the community. The impact factor for Circulation Research is 13.96. When Bolli took over as editor-in-chief, it was 9.4. From 2015 to 2016 alone, the impact factor jumped 2 points.

“Just as a major newspaper helps shape public opinion, the journal Circulation Research has an impact on what is considered important,” Bolli said. 

Impact factors are calculated by the Institute for Scientific Information and tracked by the Journal Citation Reports for more than 12,000 journals. Factors range from 0 to more than 10; only 2 percent of journal titles have a 2016 impact factor of 10 or higher.  Approximately two-thirds have a 2016 impact factor equal to or greater than 1. Those with very high impact factors include such notables as The New England Journal of Medicine and Science.

Since becoming editor-in-chief, Bolli and the Circulation Research editorial board have made dozens of changes at the journal to help increase its quality and impact factor.

“That’s a huge jump,” he said. “Four-point-five points in seven years is unprecedented. It’s very hard, as there are an increasing number of medical journals competing for articles.”

Bolli noted that the jump is even more meaningful given that Cardiovascular Research only publishes research into the cardiovascular system, where other journals publish multiple or all areas of medical research. “Our focus is much narrower, yet despite this the impact factor has gone up,” he said.

He said the impact factor of a journal is one of the main elements authors look at when deciding where to submit their best work. A journal’s ability to receive high-quality work for publication depends on how high its impact factor is, he said.

“It is a big deal to have a paper published in Circulation Research, and it is considered a significant achievement,” Bolli said.

The journal is widely read in the field, and its website receives more than 10 million hits per year. It receives approximately 2,000 submissions of articles per year, he said.

Bolli was selected as the journal’s editor-in-chief from more than 40 candidates, all leading scientists from top medical schools around the country. He called his selection an “incredible honor.”

He said that not only was it an honor for him personally, it was notable for the University of Louisville, as having the editor of a leading medical journal housed at the School of Medicine raises its profile internationally.

“I view it as my most important contribution to science, more than anything else I’ve done,” he said. “The journal helps steer the field of cardiovascular research.”

Membership on the journal’s editorial board is also very competitive, and is reserved for the top cardiovascular researchers in the world.  “It is an honor just to be included,” Bolli said.

One of the changes he and the board made was raising the bar for article acceptance. Only 7 percent of articles submitted are now accepted, compared with 16 percent before.

“If we select an article to be published, it is truly novel, methodologically immaculate, and likely to be important for others,” Bolli said.

Another change was an acceleration of the review process, making acceptance of articles more efficient. He said the journal now has the shortest turnaround time in the field. The journal also was opened up to clinical studies involving patients, and has launched more than 20 new article categories.

For Bolli, seeing the journal rise in prominence after years of hard work is meaningful not just for himself, but for the patients that ultimately benefit from research in the field.