Although the participation of women in science is increasing around the world, the physical sciences are lagging behind other fields in closing the gender gap. From 2011 to 2015, just 21% of the US physicists and astronomers who published peer-reviewed articles, reviews, or conference proceedings were women, according to a report released 8 March by the publisher Elsevier.
When considering all fields of science, the report highlights both disparities and areas of progress. Female scientists published fewer papers on average than their male colleagues, and they were less likely to publish as part of international collaborations; however, women authors tended to be cited and downloaded just as often as men.
Overall in 2011–15, about 40% of US scientific authors were women, according to the report’s data, compared with 31% for papers published from 1996 to 2000 (see graph above). Canada, Australia, and the European Union posted similar numbers, and in Brazil and Portugal the gender split was nearly 50–50. Japan was the major laggard among the 11 surveyed countries plus the EU: About 20% of Japanese authors in the sciences in 2011–15 were women, and only 11% in physics and astronomy.
The Elsevier researchers mined the names of scientists from the company’s Scopus database, which includes millions of documents and nearly 7000 physical science publications that are produced by Elsevier and competing publishers. The researchers plucked every author with a full name in the database and used resources including genderize.io, NamSor, and Wikipedia to classify each name as male or female. Each author was then assigned a country of origin based on the location of the affiliated institution listed most frequently in their first year of publication.
The authors of the report point to research by UNESCO and others showing that there is a minimal gender gap when it comes to pursuing bachelor’s and master’s degrees in the sciences; the disparity begins at the PhD stage and persists from there. But for physics the gender imbalance starts earlier in the pipeline, according to survey data from the American Institute of Physics (AIP), which publishes Physics Today. In the US, women earn about one-fifth of the bachelor’s, master’s, and doctoral degrees awarded in physics.
The 21% figure for women in US physics and astronomy mirrored the percentages in other countries and in related fields such as mathematics (21% for the US), engineering (21%), computer science (22%), and Earth and planetary sciences (24%). All the figures for 2011–15 were higher than those for 1996–2000. Because the authors did not perform statistical significance tests, it’s difficult to directly compare numbers, and the data cannot be used to predict future trends. Coauthor Rachel Herbert, a senior market intelligence manager at Elsevier, says the report should be treated as a census, with the data representing snapshots in time. The report “can be used to establish benchmarks for measuring progress going forward,” she says.
In every surveyed country except Japan, male scientists (taking into account all fields) published slightly more papers on average than female researchers (see graph at right). Men in the US who published at least one paper during the most recent five-year period churned out an average of 2.0 papers, while women produced 1.8. Male scientists also tended to publish more papers as part of international collaborations, endeavors that have been shown to yield more impactful research as measured by paper citations and downloads. Nonetheless, the Elsevier researchers find that women authors tended to publish papers that were just as impactful—and, in the US and UK, slightly more impactful—than those of their male colleagues.
The new report generates many useful statistics but doesn’t dig into the potential factors behind them. A 2015 AIP survey found that female physicists in countries including the US and Canada had access to fewer resources such as lab space and travel funding than their male counterparts did. In several other countries, women physicists were provided fewer opportunities, on average, to give talks or serve on committees. Female physicists in Japan were nearly 34 times more likely than male physicists to say that their career progression slowed after having children, the survey revealed; in fact, many Japanese men said that starting a family had no effect on their physics careers.