Trends and Influences in women authorship of randomized controlled trials in rheumatology: a comprehensive analysis of all published RCTs from 2009 to 2023

Objectives: This study aims to examine the evolution and influencing factors of women's authorship in randomized controlled trials (RCTs) published in rheumatology. Methods: This study included all rheumatology RCTs published from 2009 to 2023. The gender of authors was determined using forenames and countries of affiliation via the gender API service. The percentage of women in RCT publications and its association with potential factors was assessed using generalized estimating equations, considering women gender as the main binary outcome and the RCT's continent, international collaboration status, industrial funding, intervention type, sample size, journal adherence to ICMJE recommendations, impact factor, publication year, author's non-academic affiliation, and author position as covariates. Results: Among the 1,092 RCTs authored by 10,794 persons, women accounted for 34.1% of authors. Woman authorship was more frequent in African-based RCTs compared to North America, when the author had a non-academic affiliation and when the last author was a woman (1.83 [1.46, 2.29], +6.1 percentage points - pp). Woman authorship was less frequent in Asian and European-based RCTs, industry-funded RCTs (OR 0.64 [0.56-0.73]; -10.3pp). Women were less often in the last (0.63 [0.54-0.74]; -10.2 pp) and second to last author position (0.73 [0.62-0.85]; -7.3pp). There were no difference looking at international status or year of publication. Conclusion: The overall presence of women authors was 34.1%. The stagnant year-over-year representation of women in RCTs, and the lower likelihood of a woman having a position as senior author, underscores the need for more effective strategies to bridge the gender gap. RCTs with a woman last author were more likely to have a woman first author, suggesting a potential role-model effect.