Peer Reviewers of Medical Studies Have Conflicts of Interest

By Crystal Lindell

How much are medical studies impacted by financial conflicts of interest? New research shows the problem may run deeper than most people realize. 

The authors of peer-reviewed studies in medical journals usually have to disclose whether or not they received money from pharmaceutical companies or medical device manufacturers. But new research published in JAMA looks at the next layer: the peer reviewers themselves.

Due to the “traditionally opaque nature of peer review,” it’s difficult to investigate the issue, but an international team of researchers studied peer reviewers at high-impact medical journals like The BMJ, JAMA, The Lancet, and The New England Journal of Medicine.

They looked specifically at nearly 2,000 U.S-based physicians who served as peer reviewers. 

What they found is both unsurprising and alarming. Between 2020 and 2022, more than half (58.9%) of the peer reviewers analyzed had received at least one industry payment. In total, the peer reviewers received a staggering $1.06 billion in industry payments. 

It should be noted that companies don’t spend that kind of money out of some noble love of medicine. No, they are doing it because it helps increase their profits or advances their interests. 

Most of that money – $1 billion or 94 percent – was paid directly to individuals or to their institutions to help fund research programs. That’s why academics who churn out studies are highly prized at universities and research institutes.

The rest of the money – $64.18 million – was in the form of general payments, which includes everything from speaker fees and “honoraria” to food, drink, lodging and travel expenses. 

The median general payment to a peer reviewer was $7,614, while the median research payment was $153,173. 

Interestingly, the average male reviewer had a significantly higher total payment ($38,959) than the average female reviewer ($19,586). 

The authors also broke down differences between medical specialties. Doctors who specialize in cardiology, rheumatology, oncology, immunology or addiction treatment were the most likely to get payments (73.5%), followed by surgeons (72%), psychiatrists (65%), hospital-based specialists (47%) and primary care physicians (38%).

Those results shed light on which fields of medicine may be more susceptible to conflicts of interests.

The study’s authors came to the only conclusion that makes sense given all this data: "Additional research and transparency regarding industry payments in the peer review process are needed."

I agree that this is clearly an issue that needs to be addressed. But we shouldn’t have to wait for more research to start taking action. We need stronger policies at medical journals to help contain the potential harm it’s causing. 

At the very least, peer reviewers should have to disclose conflicts of interest. While that may conflict with the policy of some journals to keep peer reviewers anonymous, given the potential for bias and other negative consequences, it seems the financial disclosures should take precedence. 

Since peer reviewers also have the ability to reject research before it’s even published, they should have their names and potential conflicts listed in the publications. 

Beyond that, medical journals need to start having difficult conversations about whether peer reviewers should even be allowed to review studies that involve companies or industries that pay them. 

While it may not be entirely possible in our for-profit healthcare system, that doesn’t mean it shouldn’t be explored. After all, the study did not find that 100% of peer reviewers accepted payments. So clearly some peer reviewers found a way to do the work without an obvious conflict of interest.

It isn’t just medical journals that do a poor job flagging the conflicts of peer reviewers. When PNN made a Freedom of Information Act (FOIA) request to the CDC seeking more information about the “Core Expert Group” involved in the agency’s 2016 opioid guideline, most of the documents we received back were heavily edited or redacted.

The CDC’s FOIA office said the group was exempt from our request because of “deliberative process privilege” and that disclosing their conflicts would have been “a clearly unwarranted invasion of personal privacy.”  

Why Conflicts Matter

Why do conflicts of interest matter? The easiest way to understand it is that whenever money is involved, it can potentially lead to what is essentially a boss-employee power dynamic. And typically, people don’t like to upset their bosses. 

Intuitively, most people also understand that if a medical device company funds medical device research, the researchers are incentivized to manipulate both the research methods and results in hopes of providing the funder the results they seek. 

Sometimes it’s deliberate, but sometimes it just happens on a subconscious level. People naturally favor people who give them money. However, in this case, the result of that favoritism could harm the health of millions of patients. 

In one high-profile example from 2018, a top cancer researcher failed to disclose the millions of dollars in payments he received from drug and healthcare companies.

As ProPublica and The New York Times reported, Dr. José Baselga, then-chief medical officer at Memorial Sloan Kettering Cancer Center in New York, had a number of undisclosed conflicts of interests. 

One such conflict may have led Baselga to put a positive spin on the results of two Roche-sponsored clinical trials — trials that many others had considered disappointments. He did this without disclosing the more than $3 million in consulting fees he’d received from Roche. He also left out that he had a stake in a company Roche had acquired. 

Baselga resigned just days after the news investigation came out, but journalists just don’t have the resources to constantly investigate every single researcher for conflicts of interest. That’s why medical journals must regulate the issue themselves. 

Yes, most medical journals already have policies requiring study authors to disclose conflicts of interest, but as this new research makes clear, that’s not enough. It’s past time for peer reviewers to be required to do the same. 

After all, it’s not just because the public deserves to know. Our lives could depend on it. 

Medical Cannabis Provides Only Minor Relief for Chronic Pain

By Pat Anson, PNN Editor

An international team of researchers has concluded that medical cannabis and cannabinoids do not provide relief to most people with chronic pain, but are of some benefit to others.

The findings, based on a limited review of 32 medical cannabis studies, were published in the journal BMJ. They are the third set of international guidelines released this year to discourage the use of cannabis as an analgesic because clinical evidence is lacking.

“We are hopeful that patients and physicians will find our guideline helpful, and take away that while medical cannabis will not be effective for most people living with chronic pain, it may provide important benefits for a minority of patients,” said lead author Jason Busse, associate director of McMaster University’s Medicinal Cannabis Research Center in Ontario, Canada.

“For example, we found that 10% more patients that used medical cannabis vs. placebo in trials reported an important improvement in pain relief. This means that only one patient of every 10 treated with medical cannabis experienced this improvement.”

Busse and his colleagues said medical cannabis might provide a “small increase” in pain relief, sleep quality and physical function, with a “small to very small increase” in side effects such as dizziness, nausea and cognitive impairment.

It’s important to note that the panel’s recommendations do not apply patients in palliative care or to smoked or vaporized cannabis. The research team, which included a diverse group of physicians, academics and patient representatives, could not find a good quality clinical study that explored the use of inhaled cannabis.

“We hope that such trials will be forthcoming, as cross-sectional data has found many (perhaps the majority of) people living with chronic pain who use cannabis therapeutically use dried flower products that are typically inhaled or vaporized,” Busse told PNN in an email.

“The most robust evidence base is probably for use of cannabidiol (CBD) to help manage certain forms of pediatric epilepsy; however, most patients use cannabis to manage chronic pain and there are important evidence gaps that urgently need to be addressed so that patients can make fully-informed decisions.”

Due to the limited research on inhaled cannabis, the guideline’s recommendations only cover cannabis products such as edibles, sprays, oils and tinctures, which are usually low in tetrahydrocannabinol (THC), the psychoactive ingredient in cannabis that makes people high.

The panel recommended that non-inhaled cannabis or CBD only be used on a trial basis by patients when “standard care” for pain management is not sufficient. The recommendation applies to adults and children with moderate to severe chronic pain caused by cancer, neuropathy, nociceptive pain or nociplastic pain. The latter two categories cover conditions such as osteoarthritis and fibromyalgia.

“Our weak recommendation in favour of a trial of medical cannabis or cannabinoids reflects a high value placed on small to very small improvements in self reported pain intensity, physical functioning, and sleep quality, and a willingness to accept a very small to modest risk of mostly self limited and transient harms,” researchers said.

“The panel, including patient partners, believes that there is great variability in how much reduction in pain severity, improvement in physical functioning, or sleep quality each patient would consider important. Patients who place a high value in improving these symptoms by any amount are more likely to pursue a trial of medical cannabis or cannabinoids.”

The researchers recommend that patients start with a low-dose CBD product, and gradually increase the dose and THC level depending on how the patient responds.

Two medical guidelines released earlier this year also take a dim view of cannabis as a pain reliever. The Australian and New Zealand College of Anaesthetists (ANZCA) urged doctors not to prescribe medical cannabis for patients with chronic pain unless they are enrolled in a clinical trial.

The International Association for the Study of Pain also said it could not endorse the use of cannabinoids to treat pain because there was not enough evidence on the safety and efficacy of CBD.

Study Questions Value of Knee Replacement Surgery

By Pat Anson, Editor

New research is raising questions about the value of knee replacement surgeries, one of the fastest growing elective procedures in the United States.

In an analysis of over 7,400 patients with osteoarthritis who had knee replacement surgeries, researchers concluded the procedure often had minimal effects on quality of life and wasn’t worth the cost. But when the surgeries are performed on patients with more severe knee pain, their effectiveness increases, researchers reported in The BMJ.

The annual rate of total knee replacements in the U.S. has doubled since 2000, with more than 640,000 surgeries now performed annually at a cost of $10.2 billion.

"Given its limited effectiveness in individuals with less severely affected physical function, performance of total knee replacement in these patients seems to be economically unjustifiable," wrote lead author Bart Ferket, MD, an assistant professor at the Icahn School of Medicine at Mount Sinai in New York City.

"Considerable cost savings could be made by limiting eligibility to patients with more symptomatic knee osteoarthritis,"

Osteoarthritis is a joint disorder that leads to thinning of cartilage and progressive joint damage. Nearly 40 percent of Americans over the age of 45 have some degree of knee osteoarthritis, and those numbers are expected to grow as the population ages.

Ferket and his colleagues found that about a third of the patients who had their knees replaced continued to experience chronic pain after the procedure. Their quality of life generally improved, but the change was small. The improvement in quality of life was higher when patients with lower physical scores before surgery were operated on.

“The practice of total knee replacement as performed in a recent U.S. cohort of patients with knee osteoarthritis had minimal effects on quality of life. If the procedure were restricted to patients with more severe functional status, however, its effectiveness would rise, with practice becoming economically more attractive,” they concluded.

"Our findings emphasize the need for more research comparing total knee replacement with less expensive, more conservative interventions, particularly in patients with less severe symptoms.”

Previous studies have also questioned the value of many knee surgeries. A five year study of 175 knee replacement patients by the National Institutes of Health found that over a third of the surgeries were inappropriate. Many patients had pain and other symptoms that were too mild to justify having their knees replaced.  

Another study found that arthroscopic knee surgery is “not an economically attractive treatment option” compared to physical therapy, exercise and medication.

In arthroscopic surgery, a doctor makes a small incision in the knee and inserts a tiny camera and instruments to repair damaged ligaments or torn meniscus. Arthroscopic surgery is far less invasive than a total knee replacement. Depending on insurance, hospital charges and the surgeon, arthroscopic surgeries cost about $4,000.  A total knee replacement costs about $28,000 according to HealthCare Bluebook.