Mixed-gender research teams remain significantly underrepresented in science. At the same time, male-female teams are more likely to produce new and highly cited research than same-gender teams.
Both findings are from a new study in Proceedings of the National Academy of Sciences. The paper focuses on academic medicine, as its authors began writing it during COVID-19 and academic medicine is a funding giant. But when the authors did similar analyzes for medical subfields and other scientific fields, their results held.
“We did the same analysis for every other discipline in science—we did it for physics, we did it for chemistry, biology, and sociology, and again we find the same fact: mixed-gender teams do better than same-gender teams. ” said co-author Brian Uzzi, the Richard L. Thomas Professor of Leadership at Northwestern University’s Kellogg School of Management. “And the more gender balanced in a mixed-gender team, the higher the impact.”
How much better? In academic medicine, for example, Uzzi and his (mixed-gender) team found that male-female teams publish papers that are up to 7 percent younger and 15 percent more likely to be cited than papers published by men or all women’s teams.
While some previous research has compared the scientific results of women and men, Uzzi said, the result of this new study is “We are actually better together than we are apart.”
He continued, “When we started this, I thought, ‘What are we going to find? It will probably have very mixed results.’ But we weren’t sure. And when the results came out—and they were so clear and so systematic—we said, “We really found something.”
For the primary analysis of academic medicine, Uzzi and his team considered 6.6 million papers published in about 15,000 journals worldwide over 20 years. Given the size of their data set, they used a computer algorithm to determine the scientists’ genders from their names, male or female. (For this reason, the study does not speak to gender diversity beyond males and females.)
In 2000, Uzzi and his colleagues found that about 60 percent of four-person teams included men and women. By 2019, it was 70 percent. To see if this was more or less than expected based on who was doing the science, Uzzi’s team created a model that randomly swapped male and female authors who had the same first year of publication, the total number of publications and the state. Based on this model, gender diverse teams are significantly underrepresented at every team size—up to 17 percent underrepresentation.
Next, to compare the results of different-gender and same-gender teams, Uzzi and his colleagues had to settle on a definition of innovation and find a way to measure it. Guided by previous research, they defined novel papers as those that combine knowledge in a new way relative to existing combinations. Part of the way they measured it was to look at the journals referenced in a given paper, and whether those journal pairings were common or unusual.
To measure a paper’s impact, Uzzi’s team followed previous research that defined high-impact papers as those in the top 5 percent of citations for papers published in a given year. (They also considered the ongoing impact.)
Exclusion of other factors, underlying mechanisms and caveats
Could anything else explain these findings? Guided again by previous research, Uzzi and his team examined whether mixed-gender teams had different levels of expertise, networks, age diversity, and international diversity characteristics compared to same-gender teams. They found that mixed-gender teams are associated with significantly higher subject matter expertise diversity, larger network sizes, higher career age diversity, and higher geographic diversity and internationalism, among other factors. But none of these factors, when controlled, can explain the positive effects of gender diversity. Citation homophily, or the phenomenon of men citing papers by men more than papers by women and vice versa, didn’t explain it either.
Gender diversity on teams is ultimately an “unknown but powerful correlate of new and impactful scientific discoveries that increases in magnitude with the team’s gender balance,” the paper says.
Why is that so? The paper is somewhat cautious here, saying that this is an area for future research. But Uzzi and his colleagues note that existing experimental research suggests that women on a team improve information-sharing processes, such as turn-taking in conversation.
“It may also be that women provide a perspective on research questions that men do not possess, and vice versa,” the paper says, “or it may be that when a team has both female and male teammates, there are specific synergies for gender diversity .teams that are more than an addition to the team processes and information typically associated with all-women’s and all-men’s teams.
Numerous business-oriented studies have found that gender diversity makes firms more productive, but some of these studies come with caveats about context and climate. One study, for example, found that gender diversity translates into market valuation and more revenue in countries and industries where gender diversity is “normally accepted.”
Economist Sylvia Ann Hewlett, founding president of the Center for Talent Innovation, said via email Monday that “when it comes to influencing highly qualified women in innovation — in medical research and elsewhere — the secret sauce is sponsorship, not representation.” Citing research in her book The sponsor effect: How to be a better leader by investing in others (Harvard Business Review, 2019), Hewlett said that “when a woman’s value is recognized and invested in by a high-level man, he is significantly more likely—19 percent more—to find value in her ideas, to give her a seat at decision-making tables and finance her projects.” (Hewlett was talking about business, but her research may provide insight into how some research teams form and operate, too.)
Uzzi said the drawback of studying the millions of letters in total is that he and his team couldn’t dig deeper into how those teams work. But he said the conditions under which gender-diverse teams are most successful probably overlap with what “makes any science team work, which is a sense of equality and openness and embracing new and different ideas.”