Category Archives: Interesting

Study of the Week – Lessons from a Serious Medical Mistake

Source: Study of the Week – Lessons from a Serious Medical Mistake

At the heart of one of modern medicine’s greatest errors was confusing correlation and causation.

Sep 19, 2022

When I began medical training, experts felt they knew how to prevent heart disease in post-menopausal women. It was simple: extend their exposure to estrogen by giving hormone replacement therapy or HRT.

It made sense: estrogen worked in the liver to reduce levels of bad cholesterol. Rates of heart disease in women increased after menopause when estrogen levels dropped.

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And there were studies—lots of them.

In 1992, the prestigious journal, the Annals of Internal Medicine, published a meta-analysis (a combination study of studies) of hormonal therapy to prevent heart disease and prolong life in post-menopausal women.

I made a slide of the main findings and conclusions. In the right column are the many observational studies of HRT. Notice that most have estimates less than 1.00, which means that the group of women who took HRT had lower rates of coronary disease.

In the next slide I’ve highlighted the results and conclusions. Note the causal verbs.

HRT does not associate with better outcomes, it decreases the risk for coronary heart disease. I remind you that these were non-randomized comparisons of women who took HRT vs those who did not.

This had a serious effect on creating a therapeutic fashion.

Journalist Gary Taubes writes that by 2001, 15 million women were taking HRT for preventive purposes.

The exact number isn’t important; what’s important is that lots of women took preventive HRT—for years—in the absence of a proper randomized trial.

The trial finally came. JAMA published the Women’s Health Initiative trial in 2002.

It was a large trial with more than 8000 post-menopausal women in each group—HRT vs placebo. Their primary outcome was strong—heart attack or death due to heart disease. Breast cancer was a safety endpoint.

The results were stunning. Not only did HRT not prevent heart disease, it caused more heart disease, pulmonary embolisms, stroke, and breast cancer than placebo.

I did a little algebra to determine what a rate of 32 per 10,000 would look like in 2001 where 15 million women were taking HRT.

The numbers are staggering. In one year alone, HRT led to a nearly 50k women being harmed.

(An important caveat is that WHI looked at HRT for prevention.)

Two Main Lessons:

The first lesson is that bio-medicine is hard. No matter how much sense something makes, the likelihood is that it won’t work. From a Bayesian point of view, our prior expectations should mostly be pessimistic. This is especially true when it comes to preventing disease.

The second lesson is that observational research has serious limitations when it comes to making causal inference. Without random assignment, you don’t know if the comparison groups were similar.

In this case, women who decided to take HRT were likely healthier than women who did not. And it is those healthier attributes that led to the findings of lower risk.

Randomization fixes this flaw because it (mostly) balances characteristics that you can see and those that you cannot see.

And it doesn’t matter if these non-random studies contain large numbers of patients or if there are many studies. They can all be biased in the same way. A systemic bias is the same in a study of 100 or 10000 patients.

Cardiologist David Cohen succinctly states the existential problem with observational studies:

I want now to add two caveats about observational research.

It is not use-less. Observational studies can tell us things like what we are doing (e.g. the number of procedures), who we are doing these procedures on, and rates of complications. This is useful.

The second caveat is that there are groups, such as Miguel Hernan’s team, working on ways to simulate trials from observational studies. The important point here is that his target trial technique is best used in spaces where there are no randomized trials or when randomized trials are not feasible.


Medicine is replete with examples where hubris led us to cause harm.

Most often, it is over-confidence in therapies that make sense and show positive results in observational studies. Always beware of non-randomized comparisons.

The antidote is randomization. The onus is on the proponents of new therapies to show that it works in a randomized trial. In the end, this mindset will lead to far less harm.


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Democrat Candidate Vicente Gonzalez Claims Texas Special Election Was Stolen

If you claim elections are stolen, you’re an election denier and a MAGA supporter. (Ops…) Outside money? How brazen can you get? mrossol

Source: Democrat Candidate Vicente Gonzalez Claims Texas Special Election Was Stolen

By Dorothy Li, September 11, 2022

Democrat congressman Vicente Gonzalez took aim at his Republican opponent on Sept. 8, saying outside money was flooding Texas congressional races in an effort to steal the election.

Rep. Mayra Flores (R-Texas) won the election for an open seat in the 34th Texas Congressional District on June 14. She is the first Republican elected in the heavily Hispanic Rio Grande District in more than 100 years.


Gonzalez, a moderate Democrat currently representing the 15th Congressional District, will face off against Flores in the next election in November because of redistricting.

On Thursday, Gonzalez claimed the Texas special election was stolen when he attended the “go vote Blue” event in Brownsville, Texas.

“There’s millions and millions of dollars from outside our region and outside our state that are coming here to try to steal our elections and take away your value and take away the process that we rely on, which is elections,” Gonzalez said, according to Fox News.

“They stole that last election. They spent $3 million to our $250,000, they campaigned for two years, and they still only won by less than one percent,” Gonzalez said. “So, the way to turn this around is getting out and vote.”

The recording was later posted by the newly elected congresswoman on Twitter late Saturday, where Gonzalez can be seen sitting next to Rep. Adam Schiff (D-Calif.).

“Just yesterday a Democrat Representative claimed an election was stolen. That’s right, Vicente Gonzalez along with Adam Schiff claimed that our win in #TX34 was stolen,” Flores wrote in a Sept. 10 post. “Vicente Gonzalez is an election denier and we will earn our win again in November!”

Schiff’s Visit

Gonzalez shared an event photo in a Sept. 9 post, where he thanked Schiff for traveling to the state to campaign for him.

“Thank you to my friend, @RepAdamSchiff, for visiting the #RGV this week,” Gonzalez wrote. “It’s important for those in Washington to know and appreciate what South Texans have to offer and I was thrilled to show him around.”

Flores, in response, called Schiff’s visit a “desperate” attempt by the far left.

“The far left is getting pretty desperate when Adam Schiff is coming down to Texas to save Vicente Gonzalez,” she said. “The swamp is protecting one of its own.”

Flores was sworn into office on June 21, replacing former Rep. Filemon Vela (D-Texas), who resigned to work for a law and lobbying firm Akin Gump in March. Flore will hold the seat until next January unless she can beat Gonzales to serve for a full term by winning in the fall.

Darlene McCormick Sanchez contributed to the report.


Legitimizing irrational anxiety is bad medicine

Lots of ‘common sense’ from Vinay. Thank you! mrossol

Source: Legitimizing irrational anxiety is bad medicine

Sep 4 Comment Share

Medicine has always drawn a distinction between appropriate and inappropriate emotions. If someone experiences sadness, loss of appetite, and lack of desire to get out of bed, it is relevant if they just lost a spouse versus if this is simply Wednesday.

Similarly, if you take appropriate precautions when you climb Half Dome you are being reasonable, but if you refuse to climb 12 stairs out of fear of heights, you are not, and you might benefit from mental health care.

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It’s time for medical professionals to advise young, middle age, healthy people to throw away your n95, leave your C02 monitor at home and get back to life. These are not proportionate responses. You are not acting reasonably. Someone needs to tell you.

Anyone who plans on being around for the next decade has only two things guaranteed: You will definitely get Covid19 and you will definitely pay taxes.

As of Sept 2022, everyone in America has had plenty of opportunity to be vaccinated if they wish. Among those who haven’t, rates of COVID-19 are sky high. Most have had and recovered from the virus, making their risk from reinfection low. Even those who’ve been vaccinated suffered breakthrough at astonishing rates. Finally, the virus itself has drifted towards less lethality.

The IFR for Covid19 is now less than flu. Fear of long COVID is irrational. In so far as it exists, you have to accept it. In so far as it is overblown, you can ignore it. There is no good evidence boosters or Paxlovid or anything changes it. That evidence would require a clear consistent and reproducible definition. Good luck with that.

Over the next few years, COVID-19 will engulf everyone on Earth. Over the next few decades, it will engulf everyone many times over.

Given: you’re eventually going to get Covid19 and it’s less dangerous than flu, you should take all the same precautions you used to take for flu, but no more.

You definitely washed your hands in the winter back in 2019, and you should do that now. At the same time you don’t have to be excessive about it. You can do it like you did before, reasonably.

You know what you didn’t do. You didn’t carry a CO2 monitor around and have a heart attack if it goes to 1800 PPM or whatever the hell scale it uses. In fact, if you even know the scale, you might benefit to talking to someone. Twitter fills with paranoid images like this.


Pre-covid, you didn’t wear a n95 mask when you went to the grocery store. Clutching it tight if you heard someone cough. You don’t need to do that now.

You didn’t stuff a child’s face into a counterfeit, untested n95 mask. If you didn’t do it then, you shouldn’t do that today. You didn’t let mid-level school officials make up masking rules (4 days after a 3 day break— just cuz), and we should not do that now. (It has no good evidence)

You would never shield your face from an infant in daycare, for hour after hour, day after day. Doing that now is deranged. The potential downside far exceeds any potential upside.

You didn’t complain that your employer was trying to encourage people to show up to work, so they can justify paying them. Don’t do that now. It seem unreal that professors, who have been handsomely paid and never asked to take risk pre-vax, are refusing to work post-vax—- refusing to work in 2022. Will they refuse to work in 2030? The virus isn’t going anywhere.

It also lacks perspective. Pre covid your employer asked you to drive to work (or bike)— that was risk you accepted to keep the job. The employer made you take the risk of flu in order to teach. The risk here is not different at all. It is not ‘hellaciously unsafe’ it is just called life.

Pre-covid, you were willing to eat food with friends and colleagues inside. You should do that now.

The CDC has done you a disservice. It has enabled people to act irrationally by pushing Paxlovid in people in whom it was not studied. It encouraged people to mask without ever generating data if the community recommendation worked, and worse: long after it made sense. It recently encouraged healthy 20 year olds to wear an n95— that is frankly bad advice. Any covid benefit dwarfed by the downsides of making a 20 year old think they are vulnerable and weak. The CDC may be doing this for political rather than medical reasons. It caters to the most irrational pole of one political party. Alternatively, the agency is filled with work from home people— who themselves could benefit from frank advice.

Some may disagree with my prescription: If you do, you should articulate the reason. Do you really think you can avoid COVID-19 indefinitely? Are you going to carrying a CO2 monitor in 2025? How long will you continue this? Do you think it’s possible you’re acting irrationally?

At this moment in time, COVID19 is not a risk big enough to most people to justify behaving differently than you did pre-covid. When I see a healthy 20 year old wearing an n95 mask outside, I feel pity for them. They are the victim of irrational messaging, virtual signaling, tribalism, and possibly also fear and anxiety. We should encourage them to live normally, and relax.

Looking down at your Co2 monitor and snapping photos for twitter is no way to live. You need some frank advice: it’s time to stop, for your own sake and those around you.

You can also follow me on my substack: Vinay Prasad’s Observations and Thoughts

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