BMJ Public Health Retracts Controversial COVID-19 Vaccine Excess Mortality Study Citing Misinformation and Lack of Rigour
In a decisive and long-awaited action, BMJ Public Health has formally retracted a controversial 2024 study that was seized upon by vaccine skeptics and critics of pandemic restrictions as evidence that COVID-19 vaccines led to millions of deaths. The paper, originally published in May 2024, analyzed mortality records from 47 Western countries and concluded that more than three million excess deaths occurred between 2020 and 2022. Excess mortality, a term used by epidemiologists to describe the difference between observed deaths and the number that would normally have been expected based on historical trends, became a key metric during the pandemic, but the study’s interpretation of that metric quickly drew sharp criticism. In its retraction notice, the journal stated bluntly that “the discussion of causes of mortality is imbalanced, lacks rigour, and includes misinformation.” The retraction represents a major rebuke of a study that had been cited by prominent public figures, including several Republican lawmakers in the United States, who argued that the scientific establishment and government policies surrounding COVID-19 were deeply flawed, if not deceptive. While the study itself did not explicitly state that vaccines and lockdown measures were the direct cause of the excess deaths, it devoted considerable attention to the possibility that COVID-19 vaccines, which had been deployed worldwide to save lives, were responsible for a large number of “suspected adverse events.” For many researchers, the retraction was not a surprise, as the paper’s methodology and narrative were immediately challenged in the weeks after publication, but its journey through journal review, institutional investigation, and public testimony highlights the fragile line between legitimate scientific inquiry and misinformation during a public health emergency.
The study, authored by four researchers, three of whom were then affiliated with the Princess Máxima Center for pediatric oncology in the Netherlands, claimed to have identified more than three million excess deaths across Western nations over a three-year period. The authors did not only document the elevated mortality; they suggested that a meaningful proportion of those deaths could plausibly be attributed to COVID-19 containment policies and the vaccines developed to combat the virus. That framing was seized upon by vaccine skeptics, anti-lockdown activists, and political opponents of pandemic management protocols, who amplified the study across social media and in congressional hearings. The corresponding author was Saskia Mostert, described in the retraction and related reporting as an independent researcher who previously worked at the Princess Máxima Center. Her co-authors included pediatric oncologists Minke Huibers and Gertjan Kaspers, among others. At the time of publication, the study’s findings were presented as proof by some that COVID vaccines, rather than saving lives, had caused catastrophic harm. This narrative resonated in particular with critics of government-imposed public health measures, including some members of the U.S. Congress, who used the paper to question the integrity of federal health agencies and the pharmaceutical industry. The paper’s influence spread rapidly despite the fact that multiple experts pointed out flaws in its methodology and conclusions. The authors did not perform a direct causal analysis linking vaccines to the deaths; instead, they leaned heavily on speculative associations and highlighted suspected adverse events. That lack of rigorous causal evidence, critics argued, was precisely why the paper should not have been published in its original form, and why its subsequent retraction was both necessary and overdue.
Almost immediately after publication, the scientific community raised alarms. Within a month, BMJ Public Health began an investigation into the paper’s quality, prompted by concerns about the integrity of its data analysis and the imbalance of its discussion. At the same time, the Princess Máxima Center, the Dutch pediatric hospital where three of the four co-authors were employed, opened its own scientific integrity investigation. The scrutiny placed significant pressure on the researchers, and Saskia Mostert, the corresponding author, ultimately resigned from the Princess Máxima Center after the institution launched its investigation. In June 2026, Mostert testified before a U.S. congressional subcommittee, where she described the backlash against the study as “blind and irrational fury.” She alleged that the negative response was a deliberate attempt to “discredit, intimidate, isolate and silence those raising unwelcome scientific questions.” Mostert also claimed that she had been willing to revise the study in response to the journal’s concerns, but that her proposed changes were “ignored by the journal.” Her testimony painted a picture of a researcher under siege, insisting that the scientific establishment was unwilling to entertain uncomfortable ideas about vaccine safety. However, the journal’s subsequent retraction notice contradicted key elements of her account, stating that her proposed edits would have been “insufficient” to address the fundamental problems with the paper. The notice further explained that Mostert was not available to cooperate with the Princess Máxima Center’s investigation and that the BMJ initially could not contact her; when she did respond to the journal’s investigators, she reportedly said that other researchers had done most of the work. That statement undermined her position as corresponding author and raised serious questions about the division of labor and responsibility among the research team.
The retraction notice from BMJ Public Health provided detailed reasons for the journal’s decision, drawing heavily on the findings of the Princess Máxima Center’s investigation. According to the journal, the center’s report concluded that the article “pays disproportionate attention to the possibility that COVID-19 containment measures and vaccination might have caused excess mortality.” The report further noted that the existence of excess mortality during the pandemic was already known and thus not newsworthy in itself. What was problematic, according to the investigators, was the authors’ insistence on foregrounding speculative explanations for those deaths without conducting the necessary causal analyses. The report stated, “Despite the fact that the authors do not investigate the causes for excess mortality, the introduction and discussion of the article are largely focused on how to explain the excess mortality.” In other words, the paper’s framing was far more suggestive than its evidence could support. The center’s investigation also alleged that the authors cherry-picked data to support their arguments, selectively including information that aligned with their narrative while ignoring data that contradicted it. Such practices are considered serious violations of scientific integrity because they can mislead readers and distort the public understanding of complex issues. The retraction notice from BMJ Public Health emphasized that the study failed to meet the journal’s standards for rigorous, balanced, and scientifically sound research. By retracting the paper, the journal effectively removed it from the formal scientific record, although the damage had already been done in public discourse. Retractions are rare and serious events in academic publishing; they signal that a paper should not be cited or relied upon as a source of truth. In this case, the retraction was seen by many as a necessary corrective to a study that had been weaponized in political debates and spread widely online.
The broader implications of this retraction extend far beyond the authors and the journal. The study had already traveled through partisan media ecosystems, reaching audiences who were primed to believe that COVID-19 vaccines had caused widespread harm. For those audiences, the retraction may do little to change their beliefs, as misinformation often persists long after corrections are issued. One of the most troubling aspects of the episode is that it illustrates how a flawed study, once published in a peer-reviewed journal, can gain a veneer of credibility that is difficult to dismantle. Even after the journal issued its retraction, the original study remained accessible online, and many vaccine skeptics continued to cite it as evidence. Scientific American reached out to two of the study’s co-authors, Minke Huibers and Gertjan Kaspers, for comment, but no response was noted at the time of reporting. The lack of immediate response from the co-authors is not unusual in such cases, but it leaves open questions about who was responsible for the study’s design, data analysis, and final text. The retraction also raises important questions about the peer review process itself. Journals rely on reviewers to identify flawed research before publication, but peer review is not infallible, especially when papers involve politically charged topics or large datasets that are difficult to independently verify. In this case, the study underwent peer review and was published, yet its flaws were not caught until after it had already influenced public discourse. This failure highlights the need for greater scrutiny of studies that make extraordinary claims, particularly those with potential implications for public health policy.
In the aftermath of the retraction, scientific and medical communities have renewed calls for rigorous standards and for greater support of independent science journalism. The episode serves as a reminder that the public’s trust in science is fragile and can be easily undermined by studies that are later discredited. It also underscores the importance of institutions and journals acting swiftly to address allegations of misconduct, even when the process is slow and complicated. BMJ Public Health’s decision to retract the paper, while difficult, was a necessary step toward restoring integrity to the scientific record. However, the case also highlights a deeper challenge: how to prevent flawed research from being published in the first place, and how to effectively communicate corrections when they occur. Scientific American, which covered this story, has emphasized the importance of standing up for science in an era when misinformation spreads rapidly and institutional trust is under assault. The magazine’s editors have urged readers to support independent journalism and rigorous research, arguing that informed citizens are essential for making sound public health decisions. The retraction of the COVID-19 excess mortality study is a cautionary tale, but it is also a testament to the resilience of the scientific process. Despite the missteps, the system ultimately identified the flaws and removed a misleading paper from the scholarly literature. What remains now is the harder work of rebuilding trust, correcting misinformation, and ensuring that future studies are held to the highest possible standards of evidence and integrity.