A bibliometric analysis of the gender gap in the authorship of leading medical journals

Five journals sit at the top of medical publishing: The New England Journal of Medicine, JAMA, The BMJ, The Lancet, and Nature Medicine. Together they shape what counts as important in clinical research. Miguel Landa-Blanco and Christian Mejia wanted to know who was getting published in them — and whether the gender gap was closing.

The dataset

The study covered every original research article published in all five journals from 2010 to 2019: 10,558 articles in total. The authors used the genderizeR library to classify first names, successfully identifying gender for 94.1% of the 7,558 unique forenames in the dataset. They set a deliberately low probability threshold (>50%) to avoid systematically excluding names from countries where Genderize.io has less coverage.

The findings

Across the decade, women accounted for 34.5% of first authorships and 24.8% of last (senior) authorships. The gap was narrowing — first-author disparity declined by about 14.5 articles per year, and last-author disparity fell faster, at 24 articles per year — but the baseline was far from parity.

Not all journals were equal. BMJ and JAMA had the most balanced gender representation across all authorship positions. NEJM and The Lancet had the fewest women as first and second authors. Nature Medicine had the fewest women in senior positions.

Geography made it worse

The country-level data revealed stark variation. South Korea had 0% women last authors. Japan had 0.9%. Austria, 9.1%. At the other end, South Africa and India showed stronger representation. The UK, Canada, and Belgium were closing the gap fastest, while China and Israel showed stagnant or widening disparities.

The structural pattern

The gap between first authorship (34.5%) and last authorship (24.8%) told its own story. In academic medicine, first authors are typically early-career researchers doing the hands-on work; last authors are senior investigators running the lab. The ten-point drop between the two positions suggested that women were entering the pipeline but not advancing through it at the same rate — or were leaving before reaching seniority.

The study, published in Communications Medicine (a Nature portfolio journal), added to a growing body of bibliometric evidence that medicine's gender problem is not just about who enters the field, but about who gets to lead within it.