The Cochrane Collaboration publishes systematic reviews of healthcare interventions. This once magnificent organisation has now reached a point of no return from which it will disappear into oblivion because of excessive bureaucracy, protection of guild and financial interests, inefficiency, incompetence, censorship, and political expediency.¹ This is a great shame because Cochrane was very much needed. 

On Sir Iain Chalmers’s initiative, we were 77 people who gathered in Oxford in the UK in October 1993 and agreed to start the Cochrane Collaboration. I opened the Nordic Cochrane Centre in Copenhagen the same month.² 

We were very enthusiastic and successful. We formulated Cochrane’s key principles, which include cooperation, teamwork, open and transparent communication and decision-making, maximising economy of effort, scientific rigour, avoiding conflicts of interest, and being open and responsive to criticism.³ 

However, as I shall illustrate, based on my own experiences and those of close colleagues, it didn’t last long before Cochrane abandoned its ideals, and the moral decline worsened over time.

Somatostatin for Bleeding Oesophageal Varices

In 1995, I published a clinical trial report with a meta-analysis of the only three placebo-controlled trials that existed.⁴ I analysed the data blindly⁵ and did not find any effect. But many hepatologists believed somatostatin worked, and when I submitted a review to the Cochrane Hepato-Biliary Group,⁶ and updated it later when more trials had been published, I faced trouble. The peer-reviewers asked me to do 15 subgroup analyses. It is inappropriate to do this when the overall result is negative; we call it torturing your data till they confess.⁷

Moreover, our review was flawed. It was based on published, industry-sponsored trials, and the biggest trial, which did not find any effect, has never been published. I asked the investigator, Andrew K. Burroughs, to share his data with us but to no avail. 

In our most recent update, we had 21 trials (2,588 patients) and concluded that it is doubtful whether saving one-half unit of blood per patient is worthwhile.⁸ 

Somatostatin is still being used, but I don’t think it has any effect. It would be odd if a hormone had important effects on a bleeding that is often fatal. 

Of Mites and Men

Some people with asthma are allergic to house dust mites. We showed that none of the many physical and chemical methods that had been tried had any effect and quickly got our review accepted for publication in the BMJ.⁹ But the Cochrane Airways Group’s editor, Paul Jones, said he needed total certainty that our data extraction was correct. We needed to review all the trials again and to go to the group’s office in London to work there while “consulting” the editorial staff, as it was called. 

We didn’t need help from people who were less qualified than us,² and the extra work was a waste of time. It delayed publication of our review considerably, which was likely intended because in the meantime, a large trial achieved public funding amounting to £728,678. 

After we had agreed on the version to be published, Jones secretly changed our abstract. Our conclusion, that the interventions “seem to be ineffective and cannot be recommended,” was changed into, “There is not enough evidence to show …,” which suggests that if we could have included the large UK trial, we might have shown an effect.

However, we had shown, with narrow confidence intervals, that we could not have missed a worthwhile effect. In our most recent update, there is still no trace of an effect, and the large UK trial made no difference.¹⁰ With my statistical background, I knew this would be the case.

We complained about the editorial misconduct, but some years later, Jones secretly changed our abstract again. 

Even today, allergy “experts” and authorities recommend treatments they must know cannot work.² The reduction in allergens is far too small to be effective, and there are lots of mites in the environment that continue coming into the house. In 2010, an honest expert noted that wrapping the mattress in allergen-proof mattress covers can best be compared to emptying the Atlantic Ocean with a teaspoon.²

The Cochrane Airways Group also refused to change a review about smoker’s lungs and my complaint to Cochrane’s Editor-in-Chief had no effect either, even though the Cochrane review was fraudulent.² The authors implied that a combination drug lowers mortality, even though the steroid part of the drug had no role in this.¹¹

Mammography Screening, Cochrane’s Biggest Scientific Scandal

I recently described the issues in the article, “Cochrane on a suicide mission.”¹ The Cochrane Breast Cancer Group had a conflict of interest, as it was funded by the centre that offered breast screening in the country, and the editors refused to include data on overdiagnosis and overtreatment of healthy women, although these outcomes were listed in our protocol the group had published. 

In October 2001, we published the full review, including the harms, in The Lancet,¹² and the stymied review in the Cochrane Library.¹³ Cochrane’s editor John Simes lied to Lancet’s editor, Richard Horton, when he said we had agreed to the changes they had insisted on, and Horton wrote a scathing editorial that was very harmful for Cochrane’s reputation.¹⁴ It took us five years, with repeated complaints to the Cochrane authorities,¹⁵ before we were allowed to add the harms of screening to our Cochrane review.¹⁶ 

I updated the review again in 2009 and 2013. In 2023, I added more deaths, and as I anticipated big problems with the by now ubiquitous Cochrane censorship, I published these data on my website after my co-author had checked them.¹⁷ As in all our Cochrane reviews, we noted that breast cancer mortality is an unreliable outcome that is biased in favour of screening. We did not find any effect of screening on total cancer mortality, including breast cancer mortality, or on all-cause mortality (risk ratios 1.00 and 1.01, respectively). 

As I had anticipated, Cochrane killed our very minor update with absurd and excessive peer reviews by people who didn’t understand the basics of cancer screening or review methodology. Eleven people contributed to the first round of feedback, with 91 separate points spanning 21 pages.¹ 

We uploaded the review, amended as per the review comments, to a preprint server,¹⁸ which the Cochrane editor was against even though several other Cochrane updates had been prepublished. On 7 June 2024, I tweeted (@PGtzsche1):

Screening for breast cancer with mammography has been sold to the public with the claims that it saves lives and saves breasts. It does neither and increases mastectomies. In the public interest, we have uploaded our updated review as a preprint. 

This was much appreciated. Over half a million have seen my tweet. But Cochrane had a political agenda to defend mammography screening, and in February 2025, they rejected our update, although we had done our utmost to meet the unwarranted demands. The editor enclosed “some comments,” which took up 62 pages. The ”Sign-Off Editor” noted that our review might create a potentially damaging firestorm of misinformation, which was blatantly false. Another absurdity was that we were not allowed to call overdiagnosis overdiagnosis, even though official announcements and other Cochrane reviews of cancer screening had done this. 

We were accused of not having considered that screening might have a “benefit not detected.” This is how advocates of alternative medicine argue. We call it wishful thinking. 

Our appeal was rejected by an “independent” editor, Jordi Pardo Pardo from Canada, whose views on overdiagnosis were void.¹ Pardo opined that a 2024 review by David Moher and colleagues¹⁹ provided a useful example of how we could have addressed the editorial concerns. Moher is also a Canadian. He produced a poor-quality, politically expedient review that didn’t alert his readers to the fact that breast cancer mortality is a biased outcome, and he didn’t report on total cancer mortality. The authors gave estimates for the number of deaths saved (all-cause mortality) per 1,000 in various age groups, which I believe is fraudulent because screening does not reduce all-cause mortality. 

Moher et al. didn’t accept overdiagnosis as an inevitable consequence of screening, as they wrote that overdiagnosis can be associated with breast cancer screening. No, it is caused by screening. They claimed that the two Canadian trials, CNBSS, some of the best ever performed, had a high risk of bias and they based this faulty information on articles written by screening advocates who had published highly misleading, and in some cases fraudulent, papers about alleged benefits of mammography screening.¹

The reason why these screening advocates have tried to discredit the CNBSS for 33 years is that they didn’t find an effect of screening on breast cancer mortality. In 2021, radiologist Martin Yaffe, co-author of the Moher review, accused the Canadian investigators yet again of scientific misconduct, having manipulated with the randomisation, and he called for retraction of the publications.²⁰ This led the University of Toronto to conduct a formal investigation chaired by Mette Kalager, the previous leader of the Norwegian breast screening programme. 

Mette delivered her report to the university 1.5 years ago but despite my repeated requests to see the report – being one of those people Mette interviewed – the university refused. The report was released on 16 or 17 July 2025, and the university covered up for its delay by avoiding offering any dates, neither for the release, nor for the report.²¹ It was impossible to copy and paste from the report; there were ridiculous redactions; and everyone interviewed was given a fake name. I was interviewed on 14 November 2022 and was called Allen. This is not openness and transparency.

Mette concluded that “The new information does not have a credible scientific impact on the reliability of the CNBSS. The two other assessors concluded similarly, “that the evidence we found is concordant with what was previously known: that the randomization process in the CNBSS was vulnerable to subversion, but ‘even if there had been acts of subversion, they could only have been few in number and (…) could have had only a trivial effect on the study findings.”

It is a huge scandal that the university did not exonerate the researchers long ago. Insiders suspect that it was afraid of litigation by aggressive radiologists with deep pockets, a threat raised several times before.¹⁵ 

In Cochrane, the huge scandal in 2001 should have made the Cochrane leaders handle our update with the utmost care but they behaved like bulls in a China shop, wrecking Cochrane’s reputation. Cochrane’s motto, “Trusted evidence,” has become a joke. I have called for screening to be abandoned because it is harmful.²²

Cochrane Cystic Fibrosis and Genetic Disorders Group 

Dealing with this group was difficult and frustrating. In 2005, Helle Krogh Johansen, my wife, wanted to update her review of vaccines for preventing infection with Pseudomonas aeruginosa in patients with cystic fibrosis. As the first author on the review, Mary Keogan, did not respond to her emails, and as there needed to be at least two authors on a Cochrane review, Helle wanted to involve me. 

The group replied that it is a conflict of interest to be married and encouraged Helle to find a co-author from another country “to reflect the international aspect of the Collaboration.” 

Helle and I have published 8 Cochrane reviews together, in other Cochrane groups, and after I had protested, I was allowed to join her. This led to fundamental and much-needed changes to the review, but Keogan became very annoyed when we sent her the review and withdrew her authorship. 

Helle was therefore surprised when she, in June 2006, discovered that Keogan was listed in the byline as co-author of our published update. Moreover, this was internally inconsistent. We wrote in the acknowledgement that Keogan was an author on previous versions, and the coversheet said that “As from Issue 1, 2006, MK was no longer involved with the review.” 

It was editorial and scientific misconduct to add Keogan’s name behind our backs, as she had not approved the fundamentally changed manuscript. The group’s excuse, that it was their policy to keep earlier authors on the byline until a substantive update was published, was void.

Six months later, the group sent us some literature searches we had not asked for. We replied it was not a good idea to require annual updates; that we all need to consider very carefully how we spend our limited resources (a Cochrane principle is maximising economy of effort); and that we were not surprised that there were no new trials, as we knew the area and the researchers well.

After another year, we updated the review.²³ There were only two large trials, and as one of them was unpublished, we asked the company, Crucell N.V., to send us the clinical study report, or at least an abstract. As we did not get any replies to our emails, we sent a registered letter by post. Crucell required that we enter a legal agreement that gave them the right to comment on the manuscript and veto the use of their data.

We don’t enter censorship agreements and replied that Crucell had explained in a press release 1.5 years earlier that the company had suspended clinical development of its vaccine. We also noted that not publishing trial results is scientific misconduct,²⁴ which shows disdain for the patients who volunteer to take part in the trial to help science progress and to help other patients. 

We did not get any data. When we submitted the update, we were told that we had agreed to recruit a new third co-author. We replied that we had wanted to include the person who was responsible for the large unpublished trial, but as we had no data, we could not do this.

We updated the review again in 2013. It was a lot of work for concluding that “Vaccines against Pseudomonas aeruginosa cannot be recommended,” based on only three trials (996 patients). 

Intravenous Alpha-1 Antitrypsin 

This drug is used for patients with lung disease caused by inherited alpha-1 antitrypsin deficiency. In 2008, it cost up to €116,000 annually per patient and as its benefit was uncertain, the Committee on Health in the Danish Parliament asked me to review the trials. 

There was no convincing evidence that the drug worked. But in the media, the Board of Health took the credit for having saved a huge amount of money for Danish taxpayers. My name was not mentioned even though I had saved at least €30 million annually.²

When I decided to do a Cochrane review with Helle, the Cochrane editors required that we recruit a subject expert as co-author because it was “quite important that a member of the review team is a clinician practising in this field.” 

This was a terrible misjudgment. Clinicians are often the most biased people to work with, which my experiences with mammography screening and house dust mites have illustrated.² 

John Ioannidis from Stanford University, the world’s most cited medical researcher, also had negative experiences with having content area experts in a review team. We published a paper where we warned against the personal prejudices and idiosyncrasies of experts, and noted that the stronger the expertise, the stronger the prior opinion, the lower the quality of the reviews, and the less time is spent on them.²⁵ Experts tend to ignore the rigour of primary research and to praise papers of lesser quality with results that support their beliefs. This is the UFO trick. You are a cheat if you use a fuzzy photo to “prove” you have seen a UFO when a photo taken with a strong lens has shown that the object is an airplane.²⁶

The Cochrane Handbook states that “Review teams must include expertise in the topic area being reviewed and include, or have access to, expertise in systematic review methodology.”²⁷ John and I suggested the opposite and noted that we regard the theory of evolution as the most important discovery of all times but Charles Darwin had no qualifications in biology. He studied medicine, law, and theology.

Helle and I complied with Cochrane’s silly requirement by including Professor Asger Dirksen, the primary investigator for the only two trials that had been carried out. He had financial conflicts of interest but we felt we could handle him with scientific arguments.

Not so. Helle and I did all the work, and when Dirksen saw our negative results, he withdrew his authorship. The editors refused to send our research for peer review before we had found a third author who needed to be a content area expert. This would have been scientific misconduct, as we had already done all the work. 

We explained we had plenty of access to experts and that they didn’t need to be co-authors. Then the editors provided us with comments from an expert with numerous conflicts of interest in relation to the drug and said he would be willing to become a co-author. This was outrageous. One of Cochrane’s principles is to avoid conflicts of interest. 

As I couldn’t persuade the editor, Alan Smyth, to move ahead, I described the case anonymously on the discussion list of the World Association of Medical Editors. There was no sympathy whatsoever with Cochrane’s attitude. I complained to the Cochrane publication arbiters and the Editor-in-Chief, David Tovey, and the deadlock only ended when Tovey told the group to send our work for peer review without demanding a third author.

The editors did not understand elementary statistical issues either. I could not convince them that P = 0.06 spoke about as much against the null hypothesis of no difference as P = 0.03. We had both P-values in our review, and they indicated harm and benefit, respectively. I asked to have our review transferred to another Cochrane group, which published it.²⁸ 

In 2020, the Danish Medical Council recommended the drug because of a “reasonable relationship between the value of the medicine and the costs of the treatment.”²⁹ How is this possible for a drug that doesn’t work and is obscenely expensive? Only one new trial had appeared; it is of an inhaled drug; and there were more exacerbations, more adverse events, and more dropouts on drug than on placebo.³⁰ 

Our Reviews of the Placebo Effect and General Health Checks Were Uneventful

We submitted our reviews of the placebo effect and general health checks to the Cochrane Consumers & Communication Review Group and the Cochrane Effective Practice and Organisation of Care (EPOC) Group, respectively. In these groups, there were no content area experts to screw up the whole process, exactly what John and I had wanted for all of Cochrane, and we did not encounter any difficulties. 

The usefulness of a paper can be judged by the number of previous papers it renders superfluous. On that count, our placebo review was outstanding, as it threw overboard 46 years of placebo research.³¹ We shared the common belief that there are important placebo effects, but this was not what we found. We included 130 trials, and placebo had no significant effect on binary outcomes. For continuous outcomes, the effect decreased with increasing sample size, suggesting the small trials were particularly biased (all trials were biased because you cannot blind a comparison between a placebo and no treatment). Even so, the only significant effect we found, on pain, was far too small to be of any relevance.²

Our review was threatening to people who had built their careers on the placebo effect, and we spent quite some time during the next six years refuting flawed or erroneous analyses and invalid arguments.² Even today, flawed papers claiming large placebo effects are being published. Just as in the 1955 JAMA article, “The powerful placebo,” the worst articles estimate the placebo effect as the before-after difference in patients in a placebo group of a randomised trial, which ignores the spontaneous improvement.

The myth about the powerful placebo won’t go away, and it is particularly strong in psychiatry. Psychiatrists routinely mistake the before-after difference for a placebo effect.³² They also call the effect of a good doctor-patient relationship a placebo effect, but this is a kind of psychotherapy.³² 

Regular Health Checks

Our review of regular health checks, called annual physicals in the United States, also came to unexpected results. We published our review in 2012 and updated it in 2019.³³ There was no reduction in total mortality (risk ratio 1.00), cardiovascular mortality (risk ratio 1.05), cancer mortality (risk ratio 1.01), or benefits for other clinical events. With 21,535 deaths, our results are very convincing. General health checks are harmful, as they lead to overdiagnosis and overtreatment and to psychological problems when people are told they are less healthy than they think.

Our review saved billions of crowns for Danish taxpayers whereas in the UK, where health checks were part of the national health service, the government didn’t care the least about the data.² The UK programme was based on evidence until our review showed it didn’t work. Then, the programme was based on “expert guidance” instead. 

In response to repeated calls for the programme to be scrapped, Public Health England announced that an expert panel would be established to review its effectiveness and value-for-money, and modeling would be used. The arguments were so bizarre that I wrote that an expert panel is the modern version of the Oracle in Delphi and that statistical modelling is like whispering in a wizard’s ear which result you would like to hear.^2,34

Despite all the “Yes, Minister” manoeuvres, people paid attention to our review and the media interest was phenomenal.² Many websites started questioning health checks. 

Psychiatric Drugs

It can be equally hard to come off depression pills as to come off benzodiazepines³² and when I proposed in 2016 to do a review of methods to help patients succeed, psychiatrist Rachel Churchill, editor of the Cochrane depression group, showed great interest.² 

However, it took nine months before we got any feedback on our protocol, and the group raised their demands along the way to levels we couldn’t possibly meet.² After two years, when we had submitted three revisions of the protocol, we received 13,874 words of comments from four editors and four peer reviewers, eight times as many words as in our protocol, and Churchill rejected the protocol. 

The 8^th and last peer review was an excuse to get rid of us. It is one of the worst I have ever seen, and, in contrast to all the other reviews, it was anonymous. We asked for the reviewer’s identity, but our hangman remained invisible, in contrast to Cochrane principles.

The hangman protected the interests of the psychiatric guild and the drug industry by denying a long array of scientific facts and using strawman arguments attacking statements we had never made.² Many demands were irrelevant, e.g. we should explain how the drugs worked, note that some antidepressants may be more effective than others, and add marketing messages about the wonders – according to Cochrane dogma – depression pills can accomplish, which is absurd in a review about helping patients to come off drugs they don’t like.

We appealed the rejection while responding to all the comments and submitted a fourth version of our protocol. We reminded Churchill that Cochrane was about collaborating and being helpful to each other, but Cochrane’s appeal mechanism was also faulty. Rebecca Fortescue, the editor of the Cochrane Airways group, upheld the rejection decision without having seen our comments or revised protocol where we had already complied with many of the issues she raised. We were told that our stance did not reflect the international consensus and could cause alarm among review users who rely on Cochrane’s impartiality. We had not offered any “stance” and Cochrane is not about consensus but about getting the science right and helping patients. 

In March 2023, I complained to Cochrane’s Editor-in-Chief, psychiatrist Karla Soares-Weiser, about editorial misconduct and asked some simple questions she refused to answer.³⁵ The interactions I subsequently had with the Cochrane leadership were bizarre.³⁶ They did not submit my complaint to a due process, and it turned out that Cochrane has no mechanism for handling allegations of editorial misconduct in an impartial manner, which all reputable journals have. 

While our protocol was being sabotaged, another group submitted a similar protocol and Cochrane published their review in 2021.³⁷ It did not include trials comparing different withdrawal strategies, which we did, and it included many flawed studies comparing abrupt discontinuation (cold turkey) with continuation, which are irrelevant and give the false impression that the patients have relapsed and need to continue on the drugs. 

Although being less useful than our review, which we published in a medical journal,³⁸ the Cochrane review is 23 times as long. The Cochrane authors could not make any firm conclusions, which we did. A median of 50% of the patients succeeded in coming off their pill, and the length of taper was highly predictive for the success rate (P = 0.00001). We also noted that all the studies confounded withdrawal symptoms with relapse; did not use hyperbolic tapering; withdrew the drug too fast in a linear fashion; and stopped it entirely when receptor occupancy was still high. We concluded that the true proportion of patients who can stop safely must be considerably higher than 50%.

The Cochrane review declared that continuation of antidepressant treatment reduces the risk of relapse and recurrence by 50-70%, which is horribly wrong. People randomised to a cold turkey develop abstinence symptoms that are misinterpreted as relapse.³²

When we established the Cochrane Collaboration in 1993, we wanted to assist patients in their decision-making. However, the Background section was about what doctors think and the review was highly paternalistic. There was no mention that many patients want to come off the drugs, which should have been the key motivation for the authors to do their review!

The Background section was full of irrelevant marketing hype and misleading statements. To “prove” that the drugs are effective, the authors cited a totally flawed review by Cipriani et al., which did not find a clinically relevant effect but rewarded the companies that cheated the most.^2,39 The Cochrane review of escitalopram, with Cipriani as first author, also shows that Cochrane is too beholden to the industry. It claims that escitalopram is significantly more effective than citalopram,⁴⁰ which studies funded by the manufacturer, Lundbeck, had shown, but this is not possible because escitalopram is the active stereoisomer of citalopram.³² 

A 2021 Cochrane review of depression pills in children⁴¹ was also industry-friendly “Garbage in, garbage out.”⁴² The first author, Sarah Hetrick, is editor in the Cochrane group that published the review. Although she found “small and unimportant” effects, she argued that the drugs might be recommended “for some individuals in some circumstances.” Such wishful thinking can be used about all ineffective treatments. Moreover, the abstract noted that “escitalopram may ‘at least slightly’ reduce odds of suicide‐related outcomes.” The truth is that these drugs double the risk of suicide in children.³²

Almost all Cochrane reviews of placebo-controlled trials of psychiatric drugs are flawed because of withdrawal effects; because they are not sufficiently blinded; and because there are too little data on harms.³² Two Cochrane reviews performed by my employees found that every single trial ever performed of methylphenidate for ADHD was at high risk of bias.⁴³ 

In May 2015, I gave a talk at the famous Maudsley debate in London and explained in the BMJ that long-term use of psychiatric drugs causes more harm than good and that the drugs should be used very sparingly.⁴⁴ I had informed my Cochrane colleagues in advance as a courtesy, but my kindness was not returned. The same day my article appeared, Cochrane’s Editor-in-Chief, David Tovey, and the three editors in charge of the three Cochrane mental health groups, attacked my scientific credibility on BMJ’s website.⁴⁵

BMJ published a foolish news item, “Cochrane distances itself from controversial views on psychiatric drugs.”⁴⁶ It is not controversial that scientists tell the public what they know, and a news channel got it right: “Unable to counter Gøtzsche’s arguments in any rational or scientific manner, organized psychiatry, and, alas, members of the Cochrane Collaboration itself, have disgraced themselves with suspiciously speedy and mendacious denigrations of his work.”⁴⁷

Carl Heneghan, Director of the Centre for Evidence-Based Medicine in Oxford, said that Cochrane’s actions towards me were very damaging.² If Cochrane doesn’t like what you say, you will get a public renunciation. Nobody wants to risk that.

Carl and his close colleague, Tom Jefferson, recently noted that the Cochrane Collaboration is over.⁴⁸ Those who, like me, were elected for the Cochrane Governing Board and tried to hold Cochrane to account were ridiculed and sidelined, and in 2018, I was expelled from the board and from Cochrane as the only person ever.⁴⁹ Why? Because I pointed out the “organisation’s shift towards a commercial business model approach, away from its true roots of independent, scientific analysis and open public debate.”⁴⁸

The Cochrane Show Trial, Perhaps the Worst Ever in Academia

I was expelled from Cochrane after a show trial of the worst calibre, where the Cochrane leaders broke every essential rule for charities and for Cochrane, used falsified evidence planted by co-chair of the board, Martin Burton, and lied about me during the secret board meeting and afterwards.^2,49 

John Ioannidis published a scathing criticism of Cochrane’s leadership,⁵⁰ and BMJ’s editor Fiona Godlee hit the nail on the head when she wrote that Cochrane should be committed to holding industry and academia to account, and that my expulsion from Cochrane reflected “a deep seated difference of opinion about how close to industry is too close.”⁵¹ Even today, you can be a Cochrane author despite getting money directly from the company whose product you are evaluating.²

During the show trial,⁴⁹ board member David Hammerstein said that every single conflict between the central executive board and me was about an issue where the board took the side of the pharmaceutical industry. He warned that Cochrane was setting a dangerous precedent whereby industry representatives only had to “write a complaint to Cochrane and then Cochrane caves in under the pressure.” He also said that Cochrane leaders had told him it was about the money, not about getting the science right: “What the Nordic Cochrane Centre does bothers a lot of very powerful people.” 

When I published my much-acclaimed book about organised crime in the drug industry in 2013,⁵² Cochrane’s newly appointed CEO, journalist Mark Wilson, denounced it, e.g. by writing to Danish psychiatrists that the “views” in my book were not the views of Cochrane. Well, my “views” were not views but thoroughly documented facts. 

To celebrate Cochrane’s 20^th anniversary in 2013, science journalist Alan Cassels was asked to write a book about Cochrane. He interviewed many people, but in February 2013, he wrote to Tom and me that he considered us the most trusted people in Cochrane and wanted to share the bad news with us first. Wilson had killed his book saying he should have been much more critical of my work and that “there was too much Peter Gøtzsche” in it. But Alan had written a book about the most essential events in Cochrane’s history, not about those with the most shoulder stripes. I offered economic support to get the book out, but Alan found another publisher.⁵³ 

Even though the Cochrane Spokesperson Policy encourages criticism of Cochrane reviews, I have experienced many times that editors or authors refused to publish my criticisms within the reviews, with a reply from the authors, and refused to change reviews even when they were wrong or even fraudulent.^2,11 

In 2001, we published a review of the quality of 53 new Cochrane reviews in the BMJ.⁵⁴ We found that the evidence did not fully support the conclusion in nine reviews (17%), and all the problematic conclusions were too favourable for the experimental intervention. We informed our Cochrane colleagues in advance of the publication so that they could prepare for questions from journalists.³⁶ But our kindness was abused. The Cochrane Steering Group put substantial pressure on me not to publish our results. I argued that this would be an act of censorship and explained that it was important for patients, doctors, and others to be warned that they needed to read more than just the conclusion or the abstract.

I did what the Spokesperson Policy encouraged and was thanked for my efforts by being expelled. Instead of maintaining scientific integrity, Wilson was consumed with promoting the Cochrane brand and products and demanded censorship of dissenting views. He has left Cochrane, but the attitude has not changed. Wilson was in full control of the Cochrane Governing Board and gave them the ultimatum that they either sack him or me.^2,49 

When Tom, my PhD student Lars Jørgensen, and I showed that the Cochrane review of the HPV vaccines had missed at least 25,000 randomised females and serious harms of the vaccines and published our observations,⁵⁵ we were heavily attacked by Cochrane’s Editor-in-Chief and his deputy. They declined an offer to counter our criticism in the same journal and instead attacked us on Cochrane’s website, which is unscientific, and they even used arguments they knew were false.² 

It played a major role for my expulsion that I had criticised this prestigious Cochrane review.^2,49 My 2025 book about the HPV vaccines documents that we were right and Cochrane was wrong.⁵⁶ Many people told me they lost their high regard for Cochrane reviews because of the HPV vaccine review and the way Cochrane marketed it, like a drug company.^2,49 

More Political Expediency

I consider the sagas about our reviews on mammography screening and withdrawal of depression drugs the final nails in the coffin that marks the requiem for Cochrane. 

But there are many nails in that coffin. The psychiatrists who authored a Cochrane review of depressed elderly wrote that “there is no evidence to suggest that ECT causes any kind of brain damage.”⁵⁷ ECT causes memory loss in most patients, permanent memory loss in some, and kills about one in a thousand, which means that the brain is killed, too.⁵⁸

At the start of the Covid-19 pandemic, Tom updated his 2006 Cochrane review about physical interventions to reduce the spread of respiratory viruses. However, Cochrane held it back for 7 months and in this period, many countries mandated the use of face masks while other Cochrane researchers produced unacceptable pieces of work, using substandard studies, that gave the “right answer.”⁵⁹

This was censorship of the worst kind. The only reason to postpone publication was political expediency. The Cochrane leaders knew perfectly well how important the review was, and it became the most downloaded review in Cochrane’s history.⁶⁰ 

When Tom updated his review in 2023,⁶¹ Cochrane committed editorial misconduct again. An influencer who didn’t know much about masks or science⁶² claimed in the New York Times that masks worked, and that Cochrane’s mask review had misled the public.⁶³ Her article was full of errors, but Cochrane’s Editor-in-Chief, Karla Soares-Weiser, apologised⁶⁴ the same day on Cochrane’s website for the wording in the review summary,⁶⁵ even though there was nothing to apologise for.^2,66 She also violated Cochrane’s rules for post-publication criticism, which should have been published alongside Tom’s review, with his reply, and she didn’t even inform Tom about what she would write before she rushed into action.⁶² Adding insult to injury, Cochrane’s statement was interpreted widely as an apology coming from the authors, and some people believed the review was retracted.

After Tom in a Cochrane review had not found any effect of influenza vaccines on mortality in elderly people, a group of researchers “rearranged” the data “after invitation from Cochrane”⁶⁷ and reported that the vaccine reduced deaths⁶⁸ – an amazing statistical stunt considering that the risk ratio was 1.02 and only four people died. 

Cochrane also failed badly in its review of the Covid-19 vaccines.⁶⁹ The authors said there was little or no difference in serious adverse events compared to placebo, but when Peter Doshi and colleagues used regulatory data to reanalyse the pivotal mRNA trials, they found that one serious adverse event occurred for every 800 vaccinated people.⁷⁰ They also found that the harm was considerably larger than the benefit – avoiding hospitalisation. Doshi’s criticism of the Cochrane review, which is published within the review, is so serious that it is fair to call the Cochrane review⁷¹ a politically expedient garbage in, garbage out exercise. 

When Peter Aaby, an outstanding vaccine researcher, had found that the trivalent diphtheria, tetanus, and pertussis (DTP) vaccine increases overall mortality in low-income countries, the WHO asked key Cochrane people to assess the evidence.² The WHO was worried about what they might find out and did not allow the researchers to produce meta-analyses of the studies. Cochrane should not have accepted such unacceptable interference with its research but they complied with the demands and produced a flawed report that included vote counting – how many studies are for and how many against? – which is a method recommended against in the Cochrane Handbook.²⁷ One of the authors was Cochrane’s Editor-in-Chief, Karla Soares-Weiser, and another was statistician Julian Higgins, editor of the Cochrane Handbook. I was asked by a lawyer in New York to assess the evidence and my investigations supported Aaby’s findings and documented the many flaws in the Cochrane report.⁷² 

Cochrane also tries to be religiously expedient even though religion is the antithesis of science. Distant healing includes prayer, and the Cochrane review of intercessory prayer,⁷³ aptly published by the Cochrane Schizophrenia Group because the review is characterised by delusional thinking, is a pillar of shame for Cochrane.⁷⁴

The Cochrane authors ignored that a suspicion of fraud had been raised against a large trial, and that the largest “trial,” published in BMJ’s Christmas issue, was meant to amuse. This trial evaluated the effect of prayer 4-10 years after the patients had either left the hospital alive or had died from their bloodstream infection. The Cochrane authors did not mention that the patients were randomised many years after their outcomes had occurred and did not discuss the likelihood that time can go backwards, or that prayer can wake the dead.

As the outcome was already known for all patients, it is wrong to give a fake study bonus points for being “double-blind.” The Cochrane authors perverted the methodological principles and made themselves laughable, which the group’s editor, Clive Adams, also did when he assured us the review wasn’t a joke.⁷⁴ We came nowhere with our criticism of this review, which should have been withdrawn.

Conclusions

In the beginning, Cochrane was characterised by collaboration and a quest for truth, challenging authorities, dogma, and corporate interests. We helped authors get even poor reviews in shape instead of rejecting them after having raised insurmountable barriers, which is now commonplace if a review threatens guild, financial, or political interests.

Cochrane has set up many odd criteria for authors that do not exist in other scientific journals and additional criteria are invented ad hoc. When a dermatologist and I reviewed soft laser therapy for unwanted hair growth, the Cochrane Skin Group required a consumer as co-author. I wondered why a woman with a hairy upper lip would be considered a good scientist. We found one, but as she didn’t contribute meaningfully, we dropped her as an author.⁷⁵

In April 2021, Professor Ken Stein, Director of the Evidence Synthesis Programme at the UK National Institute of Health and Care Research (NIHR) spoke at a webinar about the work in the UK Cochrane groups and their future funding.^2,49 He criticised Cochrane substantially for much the same reasons as I had done and emphasised that Cochrane authors should be iconoclastic. About the failing scientific integrity, Stein noted that, “This is a point raised by people in the Collaboration to ensure that garbage does not go into the reviews; otherwise, your reviews will be garbage.” Two years later, all Cochrane groups in the UK lost the funding from the NIHR, which made little Denmark, my home country, the biggest contributor to Cochrane.² 

My wife declared many years ago that Cochrane is the amateurs’ paradise. Indeed. Even though a simple programming command would prevent empty graphs from being seen and printed, it took me five years, with numerous emails and requests at meetings and to committees, before I succeeded to get empty graphs out of Cochrane reviews. It is highly unprofessional to publish many pages with no information because none of the trials had reported on the prespecified outcomes in the Cochrane protocol. The Cochrane bureaucracy is really frightening, and many outstanding scientists have left the sinking ship. 

The Cochrane amateurs don’t care about the ever-increasing workload they create for the unpaid volunteers who produce the wealth Cochrane has.⁷⁶ Some Cochrane reviews are longer than whole books. The longest I have seen, 785 pages, was about drugs used for postoperative nausea and vomiting. It included 737 trials and around 100,000 patients, and yet, there was so much bias and fraud in the trials that the authors couldn’t conclude anything about which drug was best.⁷⁷

In 2019, I was invited to give a talk at CrossFit’s headquarters in Santa Cruz in California, which I repeated in Madison, Wisconsin: “Death of a whistleblower and Cochrane’s moral collapse.”⁷⁸ I survived and am in good health, but Cochrane is not. It is moribund. 

References

1 Gøtzsche PC. Cochrane on a suicide mission. Brownstone Institute 2025; June 20.

2 Gøtzsche PC. Whistleblower in healthcare (autobiography). Copenhagen: Institute for Scientific Freedom; 2025 (freely available).

3 Principles of Collaboration: Working Together for Cochrane. 

4 Gøtzsche PC, Gjørup I, Bonnén H, et al. Somatostatin v placebo in bleeding oesophageal varices: randomised trial and meta-analysis. BMJ 1995;310:1495-8.

5 Gøtzsche PC. Blinding during data analysis and writing of manuscripts. Controlled Clin Trials 1996;17:285-90.

6 Gøtzsche PC. Somatostatin or octreotide vs placebo in bleeding oesophageal varices (Cochrane Review). In: The Cochrane Library, Issue 3. Oxford: Update Software; 1997. 

7 Mills JL. Data torturing. N Engl J Med 1993;329:1196-9. 

8 Gøtzsche PC, Hróbjartsson A. Somatostatin analogues for acute bleeding oesophageal varices. Cochrane Database Syst Rev 2008;3:CD000193.

9 Hammarquist C, Burr ML, Gøtzsche PC. House dust mites and control measures in the management of asthma (Cochrane Review). In: The Cochrane Library, Issue 3. Oxford: Update Software; 1998. 

10 Gøtzsche PC, Johansen HK. House dust mite control measures for asthma. Cochrane Database Syst Rev 2008;2:CD001187.

11 Gøtzsche PC. Fraudulent GSK trial of steroid for smoker’s lungs and Cochrane fraud, too. Copenhagen: Institute for Scientific Freedom 2025;April 24 and Gøtzsche PC. Comment on: Nannini LJ, Poole P, Milan SJ, et al. Combined corticosteroid and long-acting beta2-agonist in one inhaler versus placebo for chronic obstructive pulmonary disease. Cochrane Database Syst Rev 2013;11:CD003794 (comment published 2021; Aug 5).

12 Olsen O, Gøtzsche PC. Cochrane review on screening for breast cancer with mammography. Lancet 2001;358:1340-2 and Olsen O, Gøtzsche PC. Systematic review of screening for breast cancer with mammography. Lancet 2001; Oct 20.

13 Olsen O, Gøtzsche PC. Screening for breast cancer with mammography. Cochrane Database Syst Rev 2001;4:CD001877.

14 Horton R. Screening mammography – an overview revisited. Lancet 2001;358:1284-5.

15 Gøtzsche PC. Mammography screening: The great hoax. Copenhagen: Institute for Scientific Freedom; 2024 (freely available) and Gøtzsche PC. Mammography screening: truth, lies and controversy. London: Radcliffe Publishing; 2012.

16 Gøtzsche PC, Nielsen M. Screening for breast cancer with mammography. Cochrane Database Syst Rev 2006;4:CD001877.

17 Gøtzsche PC. Screening for breast cancer with mammography. Copenhagen: Institute for Scientific Freedom 2023; May 3.

18 Gøtzsche PC, Jørgensen KJ. Screening for breast cancer with mammography. Updated Cochrane review 2024; June 6:medRxiv preprint.

19 Bennett A, Shaver N, Vyas N, et al. Screening for breast cancer: a systematic review update to inform the Canadian Task Force on Preventive Health Care guideline. Syst Rev 2024;13:304.

20 Yaffe M. Guest post: University of Toronto should take action on flawed breast screening study. Retraction Watch 2025; April 28.

21 Kalager M. Expert Panel Review of the Canadian National Breast Screening Study (CNBSS). University of Toronto 2025. Undated, but was released on 16 or 17 July and was delivered by Kalager to the university 1.5 years earlier. 

22 Gøtzsche PC. Mammography screening is harmful and should be abandoned. J R Soc Med 2015;108:341-5. 

23 Johansen HK, Gøtzsche PC. Vaccines for preventing infection with Pseudomonas aeruginosa in cystic fibrosis. Cochrane Database Syst Rev 2008;4:CD001399.

24 Chalmers I. Underreporting research is scientific misconduct. JAMA 1990;263:1405-8.

25 Gøtzsche PC, Ioannidis JPA. Content area experts as authors: helpful or harmful for systematic reviews and meta-analyses? BMJ 2012;345:e7031.

26 Sagan C. The demon-haunted world: science as a candle in the dark. New York: Ballantine Books; 1996.

27 Higgins JPT, Green S (editors). Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0 [updated March 2011]. The Cochrane Collaboration 2011.

28 Gøtzsche PC, Johansen HK. Intravenous alpha-1 antitrypsin augmentation therapy for treating patients with alpha-1 antitrypsin deficiency and lung disease. Cochrane Database Syst Rev 2010;7:CD007851.

29 Medicinrådets anbefaling vedrørende human alfa-1-antitrypsin som mulig standardbehandling til patienter med alvorlig alfa-1-antitrypsinmangel. Medicinrådet 2020;Apr 23. 

30 Stolk J, Tov N, Chapman KR, et al. Efficacy and safety of inhaled α1-antitrypsin in patients with severe α1-antitrypsin deficiency and frequent exacerbations of COPD. Eur Respir J 2019;54:1900673.

31 Hróbjartsson A, Gøtzsche PC. Is the placebo powerless? An analysis of clinical trials comparing placebo with no treatment. N Engl J Med 2001;344:1594-602 and Hróbjartsson A, Gøtzsche PC. Placebo treatment versus no treatment. Cochrane Database Syst Rev 2003;1:CD003974. 

32 Gøtzsche PC. Critical psychiatry textbook. Copenhagen: Institute for Scientific Freedom; 2022.

33 Krogsbøll LT, Jørgensen KJ, Gøtzsche PC. General health checks in adults for reducing morbidity and mortality from disease. Cochrane Database Syst Rev 2019;1:CD009009.

34 Gøtzsche PC. “I don’t want the truth, I want something I can tell Parliament!” BMJ 2013;347:f5222.

35 Gøtzsche PC. Complaint about Cochrane editors committing editorial misconduct. Copenhagen: Institute for Scientific Freedom 2023; March 29.

36 Gøtzsche PC. Cochrane doesn’t take editorial misconduct seriously. Copenhagen: Institute for Scientific Freedom 2023; Aug 31.

37 Van Leeuwen E, van Driel ML, Horowitz MA, et al. Approaches for discontinuation versus continuation of long-term antidepressant use for depressive and anxiety disorders in adults. Cochrane Database Syst Rev 2021;4:CD013495.

38 Gøtzsche PC, Demasi M. Interventions to help patients withdraw from depression drugs: A systematic review. Int J Risk Saf Med 2024;35:103-16.

39 Gøtzsche PC. Rewarding the Companies That Cheated the Most in Antidepressant Trials. Mad in America 2018; March 7 and Munkholm K, Paludan-Müller AS, Boesen K. Considering the methodological limitations in the evidence base of antidepressants for depression: a reanalysis of a network meta-analysis. BMJ Open 2019;9:e024886. 

40 Cipriani A, Santilli C, Furukawa TA, et al. Escitalopram versus other antidepressive agents for depression. Cochrane Database Syst Rev 2009;2:CD006532.

41 Hetrick SE, McKenzie JE, Bailey AP, et al. New generation antidepressants for depression in children and adolescents: a network meta-analysis. Cochrane Database Syst Rev 2021;5:CD013674.

42 Gøtzsche PC. Garbage in, garbage out: the newest Cochrane meta-analysis of depression pills in children. Mad in America 2021; Aug 19. 

43 Storebø OJ, Ramstad E, Krogh HB, et al. Methylphenidate for children and adolescents with attention deficit hyperactivity disorder (ADHD). Cochrane Database Syst Rev 2015;11:CD009885 and Boesen K, Paludan-Müller AS, Gøtzsche PC, et al. Extended-release methylphenidate for attention deficit hyperactivity disorder (ADHD) in adults. Cochrane Database Syst Rev 2022;2:CD012857.

44 Gøtzsche PC. Does long term use of psychiatric drugs cause more harm than good? BMJ 2015;350:h2435.

45 Tovey D, Churchill R, Adams CE, et al. Rapid Response to the Maudsley debate. BMJ 2015; May 13.

46 Wise J. Cochrane distances itself from controversial views on psychiatric drugs. BMJ 2015;351:h5073.

47 Shaw MD. Pernicious low tech issues in healthcare. HealthNewsDigest.com 2015 ;May 30.

48 Jefferson T, Heneghan C. Standing by Archie Cochrane’s agenda. Substack 2024; Sept 13. 

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50 Ioannidis JPA. Cochrane crisis: secrecy, intolerance, and evidence-based values. Eur J Clin Invest 2018;Dec 5.

51 Godlee F. Reinvigorating Cochrane. BMJ 2018;362:k3966.

52 Gøtzsche PC. Deadly medicines and organised crime: How big pharma has corrupted health care. London: Radcliffe Publishing; 2013.

53 Cassels A. The Cochrane Collaboration: medicine’s best-kept secret. Gabriola: Agio Publishing House; 2015.

54 Olsen O, Middleton P, Ezzo J, Gøtzsche PC, Hadhazy V, Herxheimer A, et al. Quality of Cochrane reviews: assessment of sample from 1998. BMJ 2001;323:829-32. 

55 Jørgensen L, Gøtzsche PC, Jefferson T. The Cochrane HPV vaccine review was incomplete and ignored important evidence of bias. BMJ Evid Based Med 2018;23:165-8. See also our own review: Jørgensen L, Gøtzsche PC, Jefferson T. Benefits and harms of the human papillomavirus (HPV) vaccines: systematic review with meta-analyses of trial data from clinical study reports. Syst Rev 2020;9:43.

56 Gøtzsche PC. How Merck and drug regulators hid serious harms of the HPV vaccines. New York: Skyhorse; 2025.

57 Van der Wurff FB, Stek ML, Hoogendijk WL, Beekman AT. Electroconvulsive therapy for the depressed elderly. Cochrane Database Syst Rev 2003;2:CD003593.

58 Gøtzsche PC. Is psychiatry a crime against humanity? Copenhagen: Institute for Scientific Freedom; 2024 (freely available).

59 Demasi M. EXCLUSIVE: Lead author of new Cochrane review speaks out. Substack 2023; Feb 5.

60 https://cochrane.altmetric.com/details/141934282.

61 Jefferson T, Dooley L, Ferroni E, et al. Physical interventions to interrupt or reduce the spread of respiratory viruses. Cochrane Database Syst Rev 2023;1:CD006207.

62 Thacker P. Zeynep Tufekci’s unseemly collusion with Cochrane officials to attack scientists is falling apart. The Disinformation Chronicle 2023; Sept 8.

63 Tufekci Z. Here’s why the science is clear that masks work. New York Times 2023; March 10. 

64 Demasi M. BREAKING: Did Cochrane sacrifice its researchers to appease critics? Substack 2023; March 15.

65 Soares-Weiser K. Statement on ‘Physical interventions to interrupt or reduce the spread of respiratory viruses’ review. Cochrane 2023; March 10.

66 Gøtzsche PC. False propaganda about face masks and Cochrane editorial misconduct. Copenhagen: Institute for Scientific Freedom 2023;Sept 11.

67 Sørensen AM. Nyt studie slår fast: Ældre bør vaccineres mod influenza. Videnskab.dk 2013;Oct 28.

68 Beyer WE, McElhaney J, Smith DJ, et al. Cochrane re-arranged: support for policies to vaccinate elderly people against influenza. Vaccine 2013;31:6030–3. 

69 Demasi M. Cochrane review of covid-19 vaccines under the microscope. Substack 2023;Nov 1.

70 Fraiman J, Erviti J, Jones M, et al. Serious adverse events of special interest following mRNA COVID-19 vaccination in randomized trials in adults. Vaccine 2022;40:5798-5805.

71 Graña C, Ghosn L, Evrenoglou T, et al. Efficacy and safety of COVID-19 vaccines. Cochrane Database Syst Rev 2022;12:CD015477.

72 Gøtzsche PC. Effect of DTP vaccines on mortality in children in low-income countries. Expert Report 2019; June 19. Also available on my homepage. 

73 Roberts L, Ahmed I, Hall S. Intercessory prayer for the alleviation of ill health. Cochrane Database Syst Rev 2007;1:CD000368.

74 Gøtzsche PC. Cochrane review of intercessory prayer: a pillar of shame for Cochrane. Copenhagen: Institute for Scientific Freedom 2024; Oct 14.

75 Hædersdal M, Gøtzsche PC. Laser and photoepilation for unwanted hair growth. Cochrane Database Syst Rev 2006;4:CD004684.

76 Gøtzsche PC. What is the moral collapse in the Cochrane Collaboration about? Ind J Med Ethics 2019 Oct-Dec;4(4) NS:303-9.

77 Carlisle J, Stevenson CA. Drugs for preventing postoperative nausea and vomiting. Cochrane Database Syst Rev 2006;3:CD004125.

78 Gøtzsche PC. Death of a whistleblower and Cochrane’s moral collapse. Video of lecture for CrossFit 2019; June 9.