Who Decides What Is Medical Misinformation?

John M. Mandrola, MD


October 13, 2022

The controversial new law in California that punishes doctors for giving false information got me thinking about the state of knowledge in medical science.

California lawmakers have equated the dissemination of false information to patients as unprofessional conduct. The key word in that sentence is the modifier, false. The law defines false information as that which counters contemporary scientific consensus.

To demonstrate the folly of attempting to define "false" and "consensus," I need not write a single word about a virus. Cardiology is replete with examples.

I briefly mentioned the antiarrhythmic reversal in a previous column, but it's worth revisiting this once-in-a-lifetime lesson in greater detail.

In the mid-1960s, the late Bernard Lown, MD, organized one of the first coronary care units. The purpose was to identify and treat ventricular arrhythmias before they become dangerous. Then, in 1977, the New England Journal of Medicine published a large observational study showing a strong association of ventricular ectopy and higher death rates.

A consensus was established that good doctors should consider ventricular arrhythmia after myocardial infarction (MI) dangerous and suppress it with antiarrhythmic drugs. If you were a doctor who questioned this consensus, you were guilty of spreading false information. I remember those days; questioning authority was not welcomed.

In 1991, the CAST investigators found that the consensus was not only wrong but fatally wrong. In a trial of antiarrhythmic drugs vs placebo in post-MI patients, the absolute increase in risk for death or cardiac arrest was 3.5%. The number needed to kill using the consensus approach was 29 patients.

Protecting Women From Cardiac Disease

Between April and June 2002, 22.4 million prescriptions were written for hormone therapy (HT). Many of these were for older women who took the drug not to relieve postmenopausal symptoms but to reduce heart disease.

They took these hormones because, a decade before, expert consensus held that HT reduced cardiac events in older women. The problem was that observational studies underpinned the consensus. A good example is this large meta-analysis of observational data, which found a strong association between HT use and fewer cardiac events. How I wrote that sentence is not how the authors worded their results and conclusions.

Instead, they wrote that "there is evidence that estrogen therapy decreases risk for coronary heart disease." And "hormone therapy should probably be recommended…." Note the causal language.

Then in July 2002, the Women's Health Initiative (WHI), a randomized controlled trial. found that older women who took HT had higher cardiac event rates. The translation of WHI to younger postmenopausal women is complicated, but the consensus that doctors should prescribe HT for cardioprotective reasons was undone.

Yet a doctor in the 1990s who questioned the use of HT would have been guilty of disseminating false information. If Twitter were around then, I can imagine such an opinion might have even been construed as antiwomen.

Let's move to a more modern example. 

Thrombolytic Therapy for Stroke

There is a now consensus that early use of thrombolytic therapy should be offered to eligible patients with stroke. This consensus has ushered in the era of stroke centers. Yet debate regarding this consensus remains.

The debate centers on interpretation of the seminal trials. Neurologists, who have the benefit of being subject experts, believe the positive NINDS and ECASS III trials have established the case for early lytic therapy. The consensus is codified in guideline documents from professional societies.

Yet some of those tasked with actually giving these drugs—emergency medicine clinicians—are skeptical about the seminal trials. Their argument is that reanalyses of both NINDS and ECASS III find substantial limitations that preclude reliable conclusions.

I entered the fray in 2018 and also made the case against lytic therapy. The stroke neurologist in our hospital scolded me because I had cast doubt in the emergency medicine physicians, which may harm patients. Influential journalists felt similarly, siding with the consensus.

True vs false information in this arena is far from settled. Two recent papers—from Ravi Garg, MD, a neurologist—cast further doubt on the seminal trials. One paper finds strong evidence of randomization errors in the NINDS trial, and the other suggests that missing data from the thrombolytic trials may be an important source of bias in the meta-analyses.

I've stopped speaking locally about this debate for fear of being further labeled a disruptive physician. The California law specifically mentions COVID-19, but physicians have been sued for acting on their skepticism regarding the expert consensus of thrombolytic therapy in stroke.

Yet a neutral observer would struggle to sort out true from false information on this topic.


These examples represent just a tiny sample.

Procedures such as percutaneous left atrial appendage closure, hypothermia for post–cardiac arrest survivors, transcutaneous edge-to-edge repair for secondary mitral regurgitation, fractional flow reserve for assessment of coronary arteries, and cerebral embolic protection after transcatheter aortic valve implantation—not to mention drugs such as niacin; fibrates; vitamins A, C, E, and D; and folate—are examples where a consensus was wrong  or remains debated.

And that's just cardiology. Don't get me started on peanut allergy in kids.

It's unlikely that the California lawmakers intended to improve the public understanding of medical science.

By passing such a farcical law, they have succeeded in exposing one of the most important aspects of medicine: uncertainty always prevails over certainty—even when experts feel there is a consensus.

John Mandrola practices cardiac electrophysiology in Louisville, Kentucky, and is a writer and podcaster for Medscape. He espouses a conservative approach to medical practice. He participates in clinical research and writes often about the state of medical evidence. 

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