Mixed-gender research teams remain significantly underrepresented in science. At the same time, male-female teams are more likely to produce novel and highly cited research than are 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 started writing it during COVID-19 and academic medicine is a funding behemoth. But when the authors ran similar analyzes for medical subfields and other science fields, their results are held.
“We did the same analysis for every other discipline in science—we did it for physics, we did it for chemistry and biology and sociology, and again we find the same fact: mixed-gender teams do better than same-gender teams.” said co-author Brian Uzzi, Richard L. Thomas Professor of Leadership at Northwestern University’s Kellogg School of Management. “And the more balanced the gender is on a mixed-gender team, the higher the impact, as well.”
How much better? In academic medicine, for instance, Uzzi and his own (mixed-gender) team found that male-female teams publish papers that are up to 7 percent more novel and 15 percent more likely to be highly cited than papers published by all-male or all-female teams.
While some prior research has compared women’s and men’s scientific outcomes, Uzzi said, the takeaway from this new study is “We’re actually better together than we are separate from each other.”
He continued, “When we started this, I thought, ‘What are we going to find? It’s probably going to be 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 academic medicine analysis, Uzzi and his team considered 6.6 million papers published in some 15,000 journals worldwide over 20 years. Given the size of their data set, they used a computer algorithm to determine scientists’ genders from their names, male or female. (For this reason, the study doesn’t speak to gender diversity beyond male and female.)
In 2000, Uzzi and his colleagues found, about 60 percent of teams of four included both men and women. By 2019, it was 70 percent. To see if this was more or less than one would expect based on who was doing the science, Uzzi’s team designed a model that randomly interchanged male and female authors who had the same first year of publication, total number of publications and country. Based on this model, gender-diverse teams are significantly underrepresented at every team size—up to 17 percent underrepresentation.
Next, to compare the outputs of gender-diverse and same-gender teams, Uzzi and his colleagues had to settle on a definition of novelty and find a way to measure it. Guided by prior research, they defined novel papers as those combining knowledge in a new way relative to existing combinations. Part of how they measured that 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 prior research that defined high-impact papers as those in the top 5 percent of citations for papers published in a given year. (They are also considered continuous impact.)
Ruling Out Other Factors, Underlying Mechanisms and Caveats
Could anything else explain these findings? Guided yet again by prior research, Uzzi and his team examined whether mixed-gender teams had different expertise levels, networks, age diversity and international diversity characteristics compared to same-gender teams. They did find that mixed-gender teams are associated with significantly higher topic-related 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 for, could explain away 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 in teams ultimately is an “underrecognized yet powerful correlate of novel and impactful scientific discoveries that increases in magnitude with the gender balance of the team,” the paper says.
Why is this so? The paper is somewhat speculative 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 taking turns in conversation.
“It might also be that women provide a perspective on research questions that men do not possess and vice versa,” paper says, “or it may be that when a team has both women and men teammates, there are synergies specific to gender-diverse teams that are more than the additivity of team processes and information typically associated with all-women and all-men teams.”
Numerous business-oriented studies have found that gender diversity makes firms more productive, but some of those studies come with caveats about context and climate. One study, for instance, found gender diversity translates to market valuation and more revenue in countries and industries where gender diversity is “normatively accepted.”
Economist Sylvia Ann Hewlett, founding president of the Center for Talent Innovation, said via email Monday that “in terms of the impact of highly qualified women on 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 worth is recognized and invested in by a senior-level man, he is much more likely—19 percent more likely—to find value in her ideas, give her a seat at decision-making tables, and fund her projects.” (Hewlett was talking about business, but her research may offer some insight into how some research teams form and operate, as well.)
Uzzi said the drawback of studying millions of papers total is that he and his team couldn’t delve into how those teams actually operate. But he said that the conditions under which gender-diverse teams are most successful probably overlap with those “that make any science team operate, which is a sense of equality and openness and being embracing of new and different ideas.”