Bias amplification

Last week I had a frustrating exchange with an acquaintance over the safety of the COVID-19 vaccine.

He'd posted on social media a meme with the gist that there'd been so much waffling and we're-not-sure-ing by the medical establishment that you couldn't trust anything they said.  I guess he'd seen me post something just a few minutes earlier and knew I was online, because shortly afterward he DMd me.

"I've been waiting for you to jump in with your two cents' worth," he said.

I guess I was in a pissy mood -- and to be honest, anti-vaxx stuff does that to me anyhow.  I know about a dozen people who've contracted COVID, two of whom died of it (both members of my graduating class in high school), and in my opinion any potential side-effects from the vaccine are insignificant compared to ending your life on a ventilator.

"Why bother?" I snapped at him.  "Nothing I say to you is going to make the slightest bit of difference.  It's a waste of time arguing."

He started in on how "he'd done his research" and "just wasn't convinced it was safe" and "the medical establishment gets rich off keeping people sick."  I snarled, "Thanks for making my point" and exited the conversation.

It's kind of maddening to be told "I've done my research" by someone who not only has never set foot in a scientific laboratory, but hasn't even bothered to read peer-reviewed papers on the topic.  Sorry, scrolling through Google, YouTube, and Reddit -- and watching Fox News -- is not research.

Unlike a lot of anti-science stances, this one is costing lives.  Every single day I see news stories about people who have become grievously ill with COVID, and whose relatives tell tearful stories after they died about how much they regretted not getting the vaccine.  Today's installment -- from a man in Tennessee who has been in the hospital for three weeks and is still on oxygen -- "They told us not to worry, that it was just a bad cold.  They lied."

The problem is -- like my acquaintance's stubbornly self-confident "I've done my research" comment -- fighting this is a Sisyphean task.  If you think I'm exaggerating, check out the paper that came out this week in Journal of the European Economic Association, about some (actual, peer-reviewed) research showing that not only do we tend to gloss over evidence contradicting our preferred beliefs, when we then share those beliefs with others, our certainty we're right increases whether or not the people we're talking to agree with us.

The phenomenon, which has been called bias amplification, is like confirmation bias on steroids.  "This experiment supports a lot of popular suspicions about why biased beliefs might be getting worse in the age of the internet," said Ryan Oprea, who co-authored the study.  "We now get a lot of information from social media and we don't know much about the quality of the information we're getting.  As a result, we're often forced to decide for ourselves how accurate various opinions and sources of information are and how much stock to put in them.  Our results suggest that people resolve this quandary by assigning credibility to sources that are telling us what we'd like to hear and this can make biases due to motivated reasoning a lot worse over time."

I don't even begin to know how to combat this.  The problem is, most laypeople (and I very much include myself in this) lack the expertise to comprehend a lot of peer-reviewed research on immunology, which is usually filled with technical jargon and abstruse details of biochemistry.  And every step you take away from the actual research -- from university or research-lab press releases, to summaries in popular science magazines, to blurbs in ordinary media, to Some Guy's blog -- introduces more opinions, oversimplifications, and outright misinformation.

And I'm completely aware that Skeptophilia is also Some Guy's blog.  I will say in my own defense, however, that I do try to base what I write on the actual research, not on Tucker Carlson quoting Nicki Minaj's tweets about how her boyfriend got the COVID vaccine and afterward his balls swelled up.  (No, I am not making this up.)

So that's today's rather discouraging scientific study.  It's sad that so many of us have to become gravely ill, or watch someone we love die in agony, before we'll admit that we might have been wrong.  I'll just end with what the research -- from the scientists themselves -- has to say: the COVID vaccines are safe and effective, and the vast majority of people who have had severe COVID are unvaccinated.  The "breakthrough cases" of vaccinated people testing positive almost never result in hospitalization, and when they do, it's because of comorbidities.

But don't take my word for it.  If you honestly want to know what the research says, and you're willing to keep an open mind on the topic and shape your opinion based upon the evidence, start here.  And after that, go out and get the fucking vaccine.

Seriously.

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London in the nineteenth century was a seriously disgusting place to live, especially for the lower classes.  Sewage was dumped into gutters along the street; it then ran down into the ground -- the same ground from which residents pumped their drinking water.  The smell can only be imagined, but the prevalence of infectious water-borne diseases is a matter of record.

In 1854 there was a horrible epidemic of cholera hit central London, ultimately killing over six hundred people.  Because the most obvious unsanitary thing about the place was the smell, the leading thinkers of the time thought that cholera came from bad air -- the "miasmal model" of contagion.  But a doctor named John Snow thought it was water-borne, and through his tireless work, he was able to trace the entire epidemic to one hand-pumped well.  Finally, after weeks and months of argument, the city planners agreed to remove the handle of the well, and the epidemic ended only a few days afterward.

The work of John Snow led to a complete change in attitude toward sanitation, sewers, and safe drinking water, and in only a few years completely changed the face of the city of London.  Snow, and the epidemic he halted, are the subject of the fantastic book The Ghost Map: The Story of London's Most Terrifying Epidemic -- and How It Changed Cities, Science, and the Modern World, by science historian Steven Johnson.  The detective work Snow undertook, and his tireless efforts to save the London poor from a horrible disease, make for fascinating reading, and shine a vivid light on what cities were like back when life for all but the wealthy was "solitary, poor, nasty, brutish, and short" (to swipe Edmund Burke's trenchant turn of phrase).

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

Getting to the essence

One of the fastest-growing areas of alternative medicine is "essential oils."

Essential oils are at least something real; it's one step better than homeopathy, for example, which is charging money for water and/or sugar pills from which all biologically active compounds have been removed by serial dilution.  These oils are concentrated extracts of plants containing aromatic compounds, which the plants themselves make for a variety of reasons, including discouraging insects from eating the leaves, attracting pollinators, or encouraging animals to eat the fruits and disperse the seeds.

The claim is that these oils have positive health effects of all sorts, but when you start looking deeper, you find that a lot of times, what the essential oil companies have to say is pretty vague.  Here's one typical example, and a few representative quotes from the website:

• What are essential oils good for?  Since long ago, people have used essential oils and plant parts to improve their lives.  We’ve continued to explore their benefits today, finding that essential oils can be integrated into daily life for a plethora of purposes.
• What makes essential oils effective?...  The variety of essential oils allows you to naturally and effectively address your specific concerns.  With so many essential oils available, you can tailor them to your specific wants and needs rather than be forced to settle for a generic solution.  This makes essential oils a popular choice for those looking for the best natural solutions in the modern era.  The verstaility [sic] of essential oils is part of what has made them so popular in recent years.  People love that they can use essential oils for a variety of tasks, without having to buy multiple products.
• How do you use essential oils effectively?  Rest assured that you don’t have to be an expert to enjoy the wide array of benefits that essential oils offer.  All you really need is a basic understanding of how to apply essential oils safely and simply as part of your daily routine.

So, in essence *rimshot* -- oils are good because they've been used by people for a long time, they're all-natural, and they smell nice.  We know this because... um... reasons.  Each one is useful for something different, because they're so versatile.

[Image licensed under the Creative Commons Stephanie (strph) from Oklahoma City, USA, Teatreeoil, CC BY-SA 2.0]

The problem is, there's little scientific support for the claim that they'll accomplish anything but making you smell nice.  The site HealthLine has a page on essential oils, and you can tell they really really want to say how great they are, but can't quite find a way to do so without lying outright.  Over and over, they say things like this:

• It’s thought that certain application methods can improve absorption, such as applying with heat or to different areas of the body.  However, research in this area is lacking.
• [S]ome people claim that essential oils can exert a physical effect on your body.  However, this has yet to be confirmed in studies.
• Despite their widespread use, little is known about the ability of essential oils to treat certain health conditions.
• [D]ue to the scents of the compounds, it’s hard to conduct blinded studies and rule out biases.  Thus, many reviews on the stress- and anxiety-relieving effects of essential oils have been inconclusive.

Even so, HealthLine has a list of particular oils and what they can be used for -- which is more than a little disingenuous.

The problem is, we now know that beyond essential oils probably not doing anything positive for your health -- they can also be dangerous.

A study that came out a couple of weeks ago in the journal Epilepsy Research looked at a group of seizure sufferers in India, and found something staggering.  Here's a quote from The Academic Times that summarizes what they discovered:

[P]atients at four South Indian hospitals who had a seizure were evaluated for the use of camphor and eucalyptus essential oils.  Analyzing 350 seizure cases that spanned a four-year period, researchers found that 15.7%, or the seizures of 55 of the patients, may have been induced by the inhalation, ingestion, or topical use of essential oils.

Now, if you're gonna shout at me that this is correlation, not causation -- that the oil use may have been present in the patients, but not caused the seizures -- check out the next bit:

The patients were asked to stop their exposure to these essential oils and the products that contained them.  The researchers then followed up with the patients for a period of 1-3 years to monitor any recurrence of seizures.  All of the non-epileptic patients had been treated with anti-seizure medication, but for only two to four weeks following their first seizure, and none of them had a recurrence of seizures in the entire 1-3 year monitoring period after stopping their exposure to essential oils.  And 94% of the epileptic patients also remained seizure-free during the follow-up period.

Not proof, but certainly mighty suggestive.

A couple of years ago the journal Evidence-Based Complementary and Alternative Medicine published an article describing a comprehensive overview of essential oils and their connection to seizures.  The results: some essential oils have potential uses as anticonvulsants, but a much longer list have been associated with causing seizures.  Which, if you know any chemistry, is exactly what you'd expect; each essential oil contains a different set of compounds, so each one is going to interact with your body differently, and carry with it its own set of potential benefits and risks.  

But that's not what the people selling essential oils tell you.  Their claim is that they're all beneficial, then wave their hands around when you ask them how they know this.  (This is called the package-deal fallacy, and is exactly the same mistake a lot of anti-GMO people make; they say "GMO = bad" without acknowledging that since clearly all genes don't do the same thing, implanting said genes in other organisms isn't going to have the same effect for each, good or bad.)

And one other thing: if an alternative health practice is getting the suspicious side-eye from Evidence-Based Complementary and Alternative Medicine -- which I'd expect to be biased toward stuff like this -- it's worth listening to.

So if you're using essential oils, it might be prudent to stop.  Or at least investigate what, if anything, scientists know about the specific essential oil you like to use.  The vast majority of evidence is that other than smelling nice, they're probably not doing much for you, and there is an increasing body of data suggesting that some of them have a real potential for dangerous side-effects.

I'll just end with a quote from the inimitable Tim Minchin, who in his brilliant monologue/poem "Storm," says, "There's a name for alternative medicine that works.  It's called... medicine."

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When people think of mass extinctions, the one that usually comes to mind first is the Cretaceous-Tertiary Extinction of 66 million years ago, the one that wiped out all the non-avian dinosaurs and a good many species of other types.  It certainly was massive -- current estimates are that it killed between fifty and sixty percent of the species alive at the time -- but it was far from the biggest.

The largest mass extinction ever took place 251 million years ago, and it destroyed over ninety percent of life on Earth, taking out whole taxa and changing the direction of evolution permanently.  But what could cause a disaster on this scale?

In When Life Nearly Died: The Greatest Mass Extinction of All Time, University of Bristol paleontologist Michael Benton describes an event so catastrophic that it beggars the imagination.  Following researchers to outcrops of rock from the time of the extinction, he looks at what was lost -- trilobites, horn corals, sea scorpions, and blastoids (a starfish relative) vanished completely, but no group was without losses.  Even terrestrial vertebrates, who made it through the bottleneck and proceeded to kind of take over, had losses on the order of seventy percent.

He goes through the possible causes for the extinction, along with the evidence for each, along the way painting a terrifying picture of a world that very nearly became uninhabited.  It's a grim but fascinating story, and Benton's expertise and clarity of writing makes it a brilliant read.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

Fear, research, and Gardasil

It is a general rule of human behavior that it is way easier to make people afraid of something than it is to convince them that what they fear is harmless.

This principle works on all scales.  The dubiously-ethical "Little Albert experiment," performed back in 1920 by John B. Watson and Rosalie Raynor, showed that you can classically condition humans with no difficulty at all -- the test subject, a nine-month-old nicknamed "Little Albert," was conditioned to fear white rats.  It worked all too well.  The baby developed a fear not only of white rats, but other furry objects (including a teddy bear).

When the test subject was tracked down years later, he was found to have an irrational phobia of dogs.

You can see this same tendency working all the way up to a conditioned fear of "the other" -- other races, ethnic groups, religions, political parties -- a fear that politicians frequently capitalize on to galvanize their supporters, and which once instilled is almost impossible to eradicate.

From an evolutionary perspective, it makes some sense.  The evolutionary cost of mistakenly fearing something that's harmless is far lower than the cost of mistakenly not fearing something that's dangerous.  If from a skeptic's standpoint, the tendency is maddening, at least it's understandable.

Even knowing this, I was pretty pissed off by the reactions I saw to a recent study that was highlighted in Phil Plait's wonderful blog Bad Astronomy -- Plait's article was titled, "Gardasil: More Anti-Vax Nonsense Collapses Under the Gaze of Reality."  In it, we hear about a study that did a large-sample-size test of side effects from the anti-HPV vaccine Gardasil, and found...

... nothing.  Nada.  None of the horrible side effects you hear from the anti-vaxxers, which include complex regional pain syndrome and postural orthostatic tachycardia.  Any incidence of disorders following the administration of the vaccine was no higher than the background rate for unvaccinated teens.

Add to that the fact that Gardasil prevents infection by HPV, which is directly linked to cancer of the throat, cervix, penis, and vagina.  Of these, cervical cancer is the most common; of the 12,900 new cases of cervical cancer diagnosed each year, an estimated 4,100 women will die of it within three years of diagnosis.  So, no common adverse side effects from Gardasil, and the benefit of protecting your children from dying of cancers that are largely preventable.  No brainer, right?

Apparently not.  Here's a selection of responses I saw to the Phil Plait article:

• I don't care what the research says.  I'm not taking that kind of chance with my children.
• Nothing has no side effects.  The risk still isn't worth it.  The pharmaceutical companies cover up the dangers.
• Why would we believe this when the medical research changes daily?  Saturated fat is bad for you, then it's not.  Sugar is bad for you, then it's not.  So they tell us this vaccine is safe, tomorrow it won't be, and then it's too late because you already gave your kids the vaccine.
• Of course they say this.  Gardasil brings in millions of dollars a year.  They have a vested interest in convincing us it's safe.

And so on and so forth.  What, does the research only convince you when something is unsafe?

Let me put this as plainly as I know how.  There is no evidence that vaccinations are dangerous, and that they increase your likelihood of any of the various disorders that anti-vaxxers want you to believe are a result.  There have been repeated large-scale studies by different researchers in different research facilities that have confirmed this result over and over.  Further, do you really want to go back to the day when people died of measles, typhoid, and diphtheria, and those who survived polio were sometimes confined to an iron lung for the rest of their lives?  We now can prevent all of those diseases, and have for the first time come up with a vaccination that prevents cancer.

To refuse to have your children protected against these deadly diseases is tantamount to child endangerment.

And I would like it if, for once, people would overcome their tendency to believe fears more strongly than reassurances, and accept what the scientists have been saying for years.