‘Strategic co-authorship’ raises integrity concerns – Study

While the decline of single-author publications is often attributed to greater scientific collaboration and research complexity, evidence suggests that systemic publication pressures and metric-based evaluation systems have also created incentives for “strategic co-authorship” practices that undermine research integrity.

This was one of the main findings of a recent research study that synthesised empirical evidence from publications in peer-reviewed journals identified through searches in PubMed, Scopus, and Web of Science databases from 2000 to 2025, documenting the decline of single-author publications, the prevalence of authorship misconduct, and the systemic drivers underlying these practices.

Titled “Beyond genuine collaboration: the rise of strategic co-authorship in contemporary academic publishing”, the research study was published in Research Integrity and Peer Review on 28 April and authored by Rui Marcelino from the University of Maia in Portugal.

It draws on bibliometric analyses, prevalence surveys, and studies of academic culture and evidence-based synthesis, arguing that addressing authorship requires fundamental reforms to institutional assessment systems, enhanced editorial vigilance, and cultural change in how the academic community values research contributions.

Strategic co-authorship categories

According to the study, ‘strategic co-authorship’ practices include honorary authorship or gift authorship and publication cartels that violate established authorship criteria.

Honorary authorship – where individuals receive authorship credit without making substantial contributions – remains one of the most common forms of publication misconduct, the study finds.

It describes the scale of the honorary authorship problem as “sobering”, noting that it affects “approximately one-third to one-half of publications in some fields (depending on how strictly criteria are applied)”.

It describes publication cartels as “self-reinforcing networks” that form through “reciprocal authorship exchanges, where scholars mutually invite each other as co-authors regardless of actual involvement, with powerful incentives for sustained participation”.

“Coercive authorship”, it states, operates through mechanisms “distinct from but intertwined with publication cartels.

“While cartels rely on consensual reciprocal exchange among relatively equal-status researchers (colleagues mutually inviting each other), coercive authorship exploits power asymmetries: 28–34% of students across disciplines report compelled inclusion of senior colleagues or supervisors lacking qualifying contributions,” the study states.

Marcelino’s study states that coercive authorship impacts nearly one-third of doctoral students globally, and publication cartels have emerged as “organised responses to dysfunctional assessment systems".

It shows that the prevalence of coercive authorship varies significantly by discipline and geography, ranging from 10% in law to 49% in medical sciences.

While multiple large-scale bibliometric analyses document the systematic decline of single-author publications across disciplines and geographic regions.

Some studies document that humanities disciplines maintain substantially higher proportions of single-authored publications (remaining above 60% in some fields), while social sciences show more balanced distributions.

By contrast, natural sciences, medicine, and engineering have experienced near-complete shifts to multi-authorship, with average article authorships exceeding five to 10 authors.

“These disciplinary variations reflect fundamental differences in research methodology, funding structures, and publication traditions (for example, monographs remain predominant in humanities while journal articles dominate in sciences) rather than uniform responses to institutional pressures,” the study states.

“Yet across all disciplines, the shift toward increased co-authorship persists, reflecting broader structural forces operating across the global scientific enterprise.”

Hyperprolific authorship

According to the paper, more than 9,000 researchers worldwide now publish at least 72 papers in a single year, highlighting “a dramatic rise in hyperprolific authorship” in academia.

“While some hyperprolific output reflects legitimate large-scale collaborations, survey studies document that 18–57% of authors do not meet International Committee of Medical Journal Editors (ICMJE ) criteria, raising questions about whether this output reflects proportional intellectual contribution.”

Philip Altbach, professor emeritus and distinguished fellow at the Center for International Higher Education, Boston College, in the United States, said the study was “yet another reason why the entire system of knowledge distribution needs careful attention”.

“It is common knowledge that the academic journal system is in deep trouble – overpriced journals from monopolistic publishers, ‘fake journals’ from predatory publishers, overemphasis on ‘publish or perish’, the growing impact of AI on journal articles and others,” he told University World News.

“This valuable study is yet another aspect of the ‘journal crisis’ – a crazy expansion of co-authored articles, reflecting not collaboration in research but often attempting to ‘fix’ the system,” Altbach said.

Professor Eke Oyom Uduma, chief executive officer of the Centre for Autism and Neurodevelopmental Disorders in Nigeria, told University World News the study highlighted an “urgent need to protect authorship integrity in research, with policymakers assuming the responsibility of ensuring that research evaluation systems move beyond quantity-based metrics to quality, transparency, and verifiable individual contributions”.

Rudi Wynand de Lange , emeritus professor in visual communication at the Tshwane University of Technology in South Africa, said the study highlighted the “threat of undeserved authorship and how this misconduct undermines the trust we should have in science”.

Call for responsible assessment frameworks

Dr Lokman Meho, a professor and university librarian at the American University of Beirut in Lebanon, said the study highlighted a “growing distortion in contemporary academic publishing: the transformation of co-authorship from a genuine indicator of scientific collaboration into, in some cases, a strategic response to hyper-competitive evaluation systems”.

He said one of its most important contributions was to show that honorary authorship, coercive authorship, and publication cartels were not “isolated ethical failures” but rather “structural consequences of metric-driven research assessment systems tied to rankings, promotion criteria, funding pressures, and publication-based incentives”.

He said the findings reinforce the need for research assessment frameworks that identify integrity-related risks often overlooked by traditional rankings. Meho is the developer of the Research Integrity Risk Index (RI²), the world’s first empirically grounded, composite metric designed to identify and profile institutional-level risks to research integrity.

He told University World News the Marcelino study made an important distinction between legitimate scientific collaboration and strategic co-authorship practices that artificially inflate productivity and impact metrics.

“Its key message to higher education policymakers is that research integrity problems cannot be addressed solely through ethical guidelines or editorial oversight.

“Institutions must also reform the incentive structures that reward publication quantity and inflated collaboration metrics without adequately evaluating the authenticity and quality of scholarly contributions.

“Otherwise, these practices risk undermining trust in scientific authorship, distorting research evaluation systems, and weakening the credibility of universities and national research systems,” Meho said.

Researcher Kenneth Besigomwe of Makerere University in Uganda said the study effectively linked honorary authorship, publication cartels, and publication pressure to “broader concerns about accountability, transparency, and trust in scientific knowledge production”.

It was especially relevant in the current context of AI-assisted scholarly production, paper mills, and growing commercialisation of academic publishing, he argued.

“Importantly, it reminds universities that global research competitiveness must remain grounded in scientific credibility, ethical scholarship, and public trust.

“For African higher education systems pursuing greater global visibility and research productivity, the study highlights the risks of over-reliance on publication counts and citation metrics.

“It reinforces the need for responsible research assessment frameworks that prioritise quality, ethical contributorship, mentorship, and research integrity over purely quantitative performance indicators,” Besigomwe said.

‘It could get worse before it gets better’

David Mills, the director of Oxford University's Centre for Global Higher Education, United Kingdom, told University World News the study highlighted the “worrying implications of publishing productivism”.

“The findings are salutary,” he said. “The metrics encourage a race to publish ever more; to buy, sell and gift authorship, and to play the citation game.”

Mills said while it was important to note that strategic co-authorship was much more common in the sciences and that some of the shift to multiple authorship reflected the rise of larger research teams to address interdisciplinary challenges, the findings were nonetheless “another reminder that the global university rankings industry has created a destructive and distorting incentive culture for academic researchers”.

He said: “We all need to learn to take journal and academic citation data – and university rankings – with more than a pinch of salt.”

Mills pointed out that there were “few policy solutions in sight”.

“It is hard to imagine universities encouraging their staff to publish less. Calls to model research integrity are admirable but naive. Academic departments continue to parade their positions in global rankings.

“The big commercial publishers have growth targets to meet. Few editors have the time or inclination to implement time-intensive investigations of possible misconduct. Things could get worse before they get better.”

Positive interventions

Higher education expert, Sakhr Alhuthali, a visiting researcher at Imperial College London, also cautioned against viewing co-authorship as “entirely negative".

“Modern science is highly collaborative, and many experimental studies genuinely require large multidisciplinary teams,” Alhuthali said. “In fact, single-author papers seem limited to some review or theoretical works.”

Alhuthali said the key issue was not the number of authors itself but whether the number and roles of authors are justified by the nature of the study. “The real concern is ensuring that collaboration remains authentic, transparent, and scientifically justified,“ Alhuthali said.

Alhuthali said commercialised authorship and profit-driven academic collaborations threatened a nation’s scientific future and long-term development by “fostering intellectual dependence on other countries and undermining genuine research and innovation”.

On possible remedies, he said: “Some journals have already taken positive steps by prohibiting the addition or removal of authors after the initial submission, helping to reduce practices such as purchased authorship.

“Academic salary structures should also be reviewed regularly so that meaningful scientific contributions (especially high-quality first-author work) are adequately rewarded through legitimate institutional mechanisms rather than through unhealthy publication markets.

“In parallel, universities should strengthen oversight against paper mills and predatory publication practices, including better monitoring of suspicious solicitation emails and fraudulent academic services.”