Who Drives Pulmonology Evidence Synthesis?

Clinical medical literature originating from low-income countries and low- and middle-income countries (LMICs) remains sparse, despite these countries showing a disproportionate disease burden. Further, authors based in LMICs are underrepresented in high-impact publications, even in those based in these countries.1Ghani M. Hurrell R. Verceles A.C. McCurdy M.T. Papali A. Geographic, subject, and authorship trends among LMIC-based scientific publications in high-impact global health and general medicine journals: a 30-month bibliometric analysis.J Epidemiol Glob Health. 2021; 11: 92-97Crossref Google Scholar,2Bhat V. Ozair A. Bellur S. et al.Inequities in country- and gender-based authorship representation in cardiology-related Cochrane reviews.JACC Adv. 2022; 1100140Crossref Scopus (1) Google Scholar Similarly, gender equity in clinical literature has come under scrutiny as women continue to be less represented as authors, particularly senior authors, even in specialties where they constitute most of the workforce.3Hart K.L. Perlis R.H. Trends in proportion of women as authors of medical journal articles, 2008-2018.JAMA Intern Med. 2019; 179: 1285-1287Crossref PubMed Scopus (67) Google Scholar,4Geng F. Ren Y. Hou H. et al.Gender equity of authorship in pulmonary medicine over the past decade.Pulmonology. 2023; (S2531-0437(23)00078-8)https://doi.org/10.1016/j.pulmoe.2023.03.005Crossref Scopus (1) Google Scholar Although the representation of women in the pulmonary workforce and literature has been highlighted and is the target of concerted efforts, the geographic diversity in high-impact pulmonary literature remains largely unknown. Understanding global authorship representation is crucial to advancing efforts to improve equity. Cochrane reviews represent some of the highest-impact medical literature in pulmonology, impacting guidelines and practice worldwide.3Hart K.L. Perlis R.H. Trends in proportion of women as authors of medical journal articles, 2008-2018.JAMA Intern Med. 2019; 179: 1285-1287Crossref PubMed Scopus (67) Google Scholar Additionally, as opposed to society guidelines, their authorship is open to researchers from across the world. So, we investigated the country-wide and gender-wide authorship diversity of pulmonology-related Cochrane reviews. We searched the Cochrane Library for reviews under the topic lung and airways from inception in October 1997 till February 23, 2023. We extracted them to a comma-delineated (.csv) file and abstracted all authors' country affiliations. Then, we manually categorized countries into high-income countries (HICs) and LMICs based on the World Bank Income classification. For gender analysis, we manually searched for one webpage explicitly demonstrating each author's gender, either through a photograph or text mentioning their gender or gender pronouns. For authors whose gender could not be found manually, we used Gender-API, an automated service, and made a determination if the software had > 90% certainty of the gender. For reviews with collaborative groups as authors, we treated each group (for example, the Non-Small Cell Lung Cancer Collaborative Group) as a single author affiliated with one country and assigned the gender as group. We carried out all analyses on GraphPad software. Ethical approval was not required because this was an analysis of publicly available data not involving patients. We followed the Strengthening the Reporting of Observational Studies in Epidemiology reporting guidelines. We included 880 studies with 3,862 authors cumulatively. Of 3,893 author affiliations, the vast majority were from HICs, with only 3.8% (n = 149) being from LMICs. The United Kingdom (29.6%; n = 1,151), Australia (19.9%; n = 774), Canada (8.6%; n = 334), the United States (5.7%; n = 223), and China (4.2%; n = 164) were the five most represented countries (Fig 1). We manually ascertained gender for 90.3% of all authors (n = 3,487/3,862), with a final gender ascertainment for 96.9% of all authors (n = 3,744/3,862) after using Gender-API. Female authors constituted 43.4% of all authors (n = 1,678/3,862), 51.4% of first authors (n = 457/889), and 50.7% of senior authors (n = 445/878). The proportion of female authors steadily increased, from 27.0% (n = 20/74) from 1997 through 2000 to 53.8% (n = 270/502) from 2021 through 2023 (Fig 2). The studies included five group authors (0.12% of all authors), all based in HICs. HICs were more likely to have greater female representation compared with LMICs as coauthors (43.5% vs 32.2%; P = .0019, two-tailed χ 2Bhat V. Ozair A. Bellur S. et al.Inequities in country- and gender-based authorship representation in cardiology-related Cochrane reviews.JACC Adv. 2022; 1100140Crossref Scopus (1) Google Scholar test), first authors (52.2% vs 32.4%; P = .0099, two-tailed χ 2Bhat V. Ozair A. Bellur S. et al.Inequities in country- and gender-based authorship representation in cardiology-related Cochrane reviews.JACC Adv. 2022; 1100140Crossref Scopus (1) Google Scholar test), and senior authors (51.2% vs 35.3%; P = .044, two-tailed χ 2Bhat V. Ozair A. Bellur S. et al.Inequities in country- and gender-based authorship representation in cardiology-related Cochrane reviews.JACC Adv. 2022; 1100140Crossref Scopus (1) Google Scholar test).Figure 2Graph showing trends in gender representation of authors of Cochrane pulmonology reviews.View Large Image Figure ViewerDownload Hi-res image Download (PPT) We found dismal representation of LMICs in the authorship of pulmonology-related Cochrane reviews. This is despite LMICs bearing the greatest burden of lung diseases. LMICs demonstrate 84% of disability-adjusted life years as a result of COPD and asthma, which together constitute the vast majority of chronic respiratory diseases.5Meghji J. Mortimer K. Agusti A. et al.Improving lung health in low-income and middle-income countries: from challenges to solutions.Lancet. 2021; 397: 928-940Abstract Full Text Full Text PDF PubMed Scopus (144) Google Scholar Unfortunately, these findings are consistent with citation analyses of the most influential literature on asthma and COPD, where authorship exhibited exclusive representation from HICs,6Qu Y. Zhang C. Hu Z. et al.The 100 most influential publications in asthma from 1960 to 2017: a bibliometric analysis.Respir Med. 2018; 137: 206-212Abstract Full Text Full Text PDF Scopus (0) Google Scholar,7Gu W. Yuan Y. Yang H. Qi G. Jin X. Yan J. A bibliometric analysis of the 100 most influential papers on COPD.Int J Chron Obstruct Pulmon Dis. 2015; 10: 667-676PubMed Google Scholar as well as analyses of clinical literature in other fields.1Ghani M. Hurrell R. Verceles A.C. McCurdy M.T. Papali A. Geographic, subject, and authorship trends among LMIC-based scientific publications in high-impact global health and general medicine journals: a 30-month bibliometric analysis.J Epidemiol Glob Health. 2021; 11: 92-97Crossref Google Scholar,2Bhat V. Ozair A. Bellur S. et al.Inequities in country- and gender-based authorship representation in cardiology-related Cochrane reviews.JACC Adv. 2022; 1100140Crossref Scopus (1) Google Scholar In contrast, we found a relatively equitable distribution of women in pulmonology Cochrane reviews, including in influential first and senior authorship positions, with a closing gender gap over the decades. Women have faced significant obstacles to success in academic pulmonology. Historically, women have been less represented in pulmonology leadership and have received less professional societal recognition, out of proportion to their overall workforce representation.8Olson E.M. Kennedy C.C. Kelm D.J. Assessment of gender parity: leadership representation in pulmonary and critical care medicine.J Womens Health (Larchmt). 2022; 31: 439-446Crossref Scopus (6) Google Scholar Further, in the pulmonary literature, women constitute a disproportionate minority in authorship, and their articles have been shown to have lower chances of acceptance or citation.3Hart K.L. Perlis R.H. Trends in proportion of women as authors of medical journal articles, 2008-2018.JAMA Intern Med. 2019; 179: 1285-1287Crossref PubMed Scopus (67) Google Scholar,9Riordan L. Levine S.M. CHEST Journal Diversity, Equity, and Inclusion Work GroupInstilling diversity, equity, and inclusion in the CHEST journal community.Chest. 2023; 164: 822-825Abstract Full Text Full Text PDF PubMed Scopus (0) Google Scholar To this end, CHEST has made concerted efforts to improve representation in membership, journal authorship, and society leadership, with notable improvements being achieved.9Riordan L. Levine S.M. CHEST Journal Diversity, Equity, and Inclusion Work GroupInstilling diversity, equity, and inclusion in the CHEST journal community.Chest. 2023; 164: 822-825Abstract Full Text Full Text PDF PubMed Scopus (0) Google Scholar Although we do not have data regarding the female pulmonary workforce worldwide, over the last few decades, the proportion of female pulmonary medicine trainees and physicians in the United States has remained unchanged.8Olson E.M. Kennedy C.C. Kelm D.J. Assessment of gender parity: leadership representation in pulmonary and critical care medicine.J Womens Health (Larchmt). 2022; 31: 439-446Crossref Scopus (6) Google Scholar Thus, the improved representation of women in Cochrane pulmonology reviews may be regarded as real improvement, as opposed to a mere reflection of increased representation in the broader workforce. This trend also aligns with findings from the literature of other specialties.3Hart K.L. Perlis R.H. Trends in proportion of women as authors of medical journal articles, 2008-2018.JAMA Intern Med. 2019; 179: 1285-1287Crossref PubMed Scopus (67) Google Scholar However, this finding was tempered by the fact that in LMICs, women authors remained disproportionately underrepresented compared with their male colleagues. Thus, further efforts to bolster equity in these regions are needed desperately. More globally inclusive authorship can ensure literature that is more pertinent to problems facing LMICs. Additionally, more diverse authorship can improve the quality of research. Recognizing this, the Cochrane Collaboration has declared global diversity and inclusion as essential to its mission.10Cochrane CollaborationCochrane diversity and inclusion. Cochrane Collaboration website.https://www.cochrane.org/about-us/cochrane-diversity-and-inclusionGoogle Scholar Targeted efforts for greater involvement of authors from LMICs are needed. Possible capacity-building efforts include financial support through region-specific scholarships, greater mentorship opportunities for LMIC-based researchers, and inviting LMIC-based authorship of evidence synthesis. Finally, these efforts should ensure that women from LMICs are well represented to mirror the trend of improving female representation worldwide, perhaps by referencing prior successful HIC-based efforts in this regard. Our work is the first to analyze the global and gender-wide authorship diversity of pulmonology-related Cochrane reviews. However, it is not without limitations. We may have missed a few pulmonology-relevant reviews under other topics in the Cochrane Library, for example, articles related to infections or child health. This is likely insignificant, given that Cochrane categorizes reviews under all relevant topics.11Cochrane LibraryBrowse by topic. Cochrane Collaboration website.https://www.cochranelibrary.com/browse-by-topicDate accessed: January 26, 2024Google Scholar Our manual ascertainment of author gender for > 90% of all authors before the use of software ensured maximum accuracy. However, we relied on the historic binary gender classification, which is limited, given the increasing recognition of multiple gender identities and their implications in health care. Further research is warranted to delineate the representation of nonbinary people and to address other facets of diversity, for example, racial, ethnic, or language identities, in the pulmonary workforce and literature. In conclusion, we found poor representation of LMICs in the authorship of pulmonology-related Cochrane reviews. Further, great progress has been made, with relative parity being achieved, in the representation of women. Significant efforts must be made to ensure equitable representation of LMICs in high-impact pulmonology literature. The authors have reported to CHEST Pulmonary the following: H. K. W. serves on the advisory board of ResMed. None declared (V. B., A. K., S. K., S. B., H. S. W., M. S. A.). Other contributions: The authors thank Himsikhar Khataniar, MD, for help with the acquisition of data.