Monday, July 30, 2007

How Science Works

From reading what many of the vaccines/mercury/”toxins”/whatever-causes-autism promoters have written about the science of autism, it is clear that most of them have only the vaguest idea of what science is and how it works. Here is what I hope will be a clear and concise “debunking” of some of the more pervasive “myths” about how science works.


Vox populi:

One of the most commonly repeated misconceptions is that scientific “facts” (what scientists refer to as “generally accepted theories of reality”) are determined by popular vote. Thus you see many of the so-call autism advocates crowing about how many people “believe” their particular line of nonsense.

Unfortunately for them, reality has shown itself supremely indifferent to majority rule. For thousands of years, the majority of people were convinced that the world was flat, but that had no effect on the spherical nature of the world. For hundreds of years, the majority of people thought that the Sun revolved around the Earth – which had no effect on celestial mechanics.

So, even if seven thousand people think that Andy Wakefield’s thoroughly disproven hypothesis about measles vaccine causing autism is true, that will have no impact on the ability of the vaccine strain of measles to cause autism.

The sad fact is that the purpose of science is to discover the underlying realities of nature, not to confirm our most cherished hypotheses. When people (even people calling themselves “scientists”) set out to prove themselves right, they often overlook the data that show they are wrong. That’s why it’s so important to have independent confirmation of results.

In the end, it not the “voice of the people” that determine whether a hypothesis lives or dies, it is the “voice of the data”.


Authority figures:

As the Autism Omnibus Proceedings have shown, there are experts and there are “experts”. The plaintiffs, so far, have had the latter. It is passing strange that the people who are generally so dismissive of the findings of doctors and scientists are so willing to blindly accept whatever their doctors and their scientists say without question.

The Omnibus Proceedings should have been a golden opportunity for the parents following the advice of these “experts” (the ones who have “…found the truth…” about autism) to see how their knowledge compared to that of “mainstream” scientists (you know, the ones who are too hidebound to see the plain truth of how measles vaccine/mercury/”toxins”/immune disorders/gut problems/etc. clearly causes autism). It should have been, but for the vocal minority, it wasn’t.

Part of the problem with authority figures in autism is that the majority of parents – the grand majority, in all liklihood – have no idea what these experts are talking about. Here’s a little quiz to find out which camp you are in:

[1] If a child has a “damaged” immune system that is unable to “fight off” a viral infection (e.g. the attenuated vaccine strain of measles), what would be the effect of giving that child corticosteroids?

(a) The child will improve.
(b) The viral infection will worsen, making the child more ill or even dead.
(c) No effect

[2] When using polymerase chain reaction (PCR) to amplify the genetic material of a measles virus strain, what is the purpose of the reverse transcriptase (RT) step?

(a) It is an optional step, used in “mainstream” science only.
(b) It creates more false negative results.
(c) It copies RNA into DNA

[3] To which of the following does ethylenediamine tetraacetate (EDTA) bind with the least strength?

(a) mercury
(b) calcium
(c) magnesium

(Answers: b, c, a)

I bring this up because a number of parents I have spoken with about the Omnibus Proceedings have no idea why it was so important that the O’Leary lab had failed to do the RT (reverse transcriptase) step when they were testing for measles virus. To them, it was just another piddling technical detail that was essentially meaningless. To me, on the other hand, it was proof positive that the O’Leary results were baloney – nothing more than contamination and poor technique.

You see, the measles virus doesn’t use DNA for its genetic material, it uses RNA (single strand, negative sense) and does not go through a DNA intermediate (unlike the retroviruses). And the PCR process doesn’t amplify RNA, only DNA. So, the only way to amplify measles genetic material is to first copy it into DNA (via reverse transcriptase) and then amplify the DNA copy (cDNA).

In fact, one of the checks routinely done to rule out the possibility of contamination (or poor primer selection) is to do the test without the RT step. If you get a positive result, you know that you have a problem.

The O’Leary lab clearly had a problem.

So, what are parents to do if they lack the specialized knowledge to judge for themselves if the “experts” know what they’re talking about? Unfortunately, relying on your “gut feeling” is probably not the way to go. My experience has been that true experts in a scientific field are often not the most personable, easy to like people in the world. Some, in fact, are not good with people.

Salesmen, charlatans and confidence men, on the other hand, are marvelous with people. They have to be – it’s their livelihood. Now, this isn’t to say that a reliable expert can’t be personable and easy to trust – that’s not true. But you can’t rely on an person's charm and charisma to inform you about their accuracy.

What it often comes down to is going with the crowd. The more people who are well-informed about the field that agree with the “expert” in question, the more likely that “expert” is to be accurate. Sad to say, but the maverick who turns his back on the majority of his scientific peers is usually wrong. The very few who have turned out to be right tend to overshadow – in the public’s eye – the thousands who were wrong and simply faded into well-deserved obscurity.

One sporting gentleman on the mercury-causes-autism side has said that betting on the maverick is a long-shot with a tremendous payoff. How I wish it were so. In fact, most of the “mavericks” bucking the “mainstream” in the “alternative” autism world have already been shown to be wrong. Andy Wakefield is just one of many in that category. A more accurate analogy would be betting on a horse that has already been taken to the knacker’s and rendered into dog food, glue and baseball covers.


Science by fiat:

Another popular concept is that scientific reality can be legislated. This has been tried a number of times previously and has a dismal history. One of the most famous was the 1633 trial of Galileo Galilei, where he was forced, by threat of death, to recant his heliocentric hypothesis of the Solar system. A more recent one is the attempt by the Dover, Pa. school board to render Intelligent Design a viable hypothesis. It failed, as well.

“Science by decree” appeals to those who are absolutely convinced that there is no possibility that they might be wrong. It was supremely ironic that Andy Wakefield, facing possible censure in the UK, quoted Vaclav Havel’s famous statement: “Seek the company of those who seek the truth and run from those who have found it.” Wakefield is so clearly one of those who have “…found it…” but is unable to see that.

Science is not well suited to legislation because it needs the flexibility to change when confronted with new information. Laws must be repealed – a long and tedious process. Scientific theories and hypotheses are altered or discarded in a moment. If science needed to move at the pace of law, we would still be “texting” on parchment.

A more practical problem is when incorrect science is enshrined in law (and what other kind would need to be legislated?). We all know that the true point of the effort to make a law out of bad science is so that somebody (maybe many somebodies) will get some money. This is not inherently bad – sometimes people need and deserve governmental assistance.

But what happens when it becomes apparent that the legislated “science” is in error? What will the legislators say to those who entreated them to make the law in the first place? How receptive will they be to another group of parents who come to them, saying “Well, it turns out that vaccines weren’t the cause of autism and we need a bunch of money to research the real cause.” Do you think that any law maker is going to want to bring that before their peers?

I think that everybody knows that if the various autism “advocacy” groups had the data, they wouldn’t need to do an “end run” around science (and, curiously, the courts) to the legislature. What they are saying, in essence, is: “We can’t convince scientists, we can’t convince the courts and we can’t even convince a majority of parents with our data, so we’re asking you to force everybody to say that we’re right.”

And that’s what it really comes down to, folks - force. They’ve given up trying to prove their point; they’ve even given up trying to persuade the parents who haven’t already jumped on their bandwagon. Now they’re going to enlist the coercive power of the government to force you to pay them to do what they (the autism "advocates") think is right.

Does that seem right to you?


Prometheus

Wednesday, July 18, 2007

Let's do a study!

A reader wrote in with concerns that I was overlooking a key point of the abysmal telephonic autism "survey" - namely, showing how many unvaccinated children were available to study the interaction of vaccines and autism... or "neurological disorders" (AKA autism spectrum and ADD/ADHD).

Actually, I think that the folks at the CDC and university medical centers all over the country (and in other countries) are acutely (even painfully) aware of the number of people who aren't vaccinated.

What GR and other advocacy groups have been agitating for is a study comparing groups that don't vaccinate their children (e.g. the Amish, although they actually do vaccinate their children) with vaccinated children. The folks at GR are pushing for this despite the fact that their baloney "survey" showed no connection between autism and vaccination.

Here are a few reasons why that study wouldn't work, followed by my own "modest proposal" for a study that would work.

[1] The unvaccinated population is not necessarily the same as the vaccinated population: People who don't vaccinate their children may not be the same as those who do. In fact, studies have shown that those who don't vaccinate their children tend to be at either end of the socioeconomic and educational spectrum. It would not be valid to draw any conclusions about the impact of vaccines on autism (or ADD/ADHD) with such marked differences between the groups (apples and oranges).

[2] Selection biases: Recruiting people for a study is one of the biggest sources of error, especially when looking for something that is a public controversy. You will tend to attract more people who believe in a connection than those who do not.

[3] Inadequate power: If the GR survey is correct, about 3% of the overall population in the 4 - 17 year age range is completely unvaccinated. On the other hand, the prevalence of autism is only 0.65% in the same age range. It will be easier to detect a statistically significant difference in unvaccinated children between autistic and non-autistic groups than it will be to detect a difference in autism prevalence between vaccinated and unvaccinated children.

[4] Loss of useful information: It would be a shame to spend the time and money to do a study and only be able to answer a single question. After all, if there is no connection between autism and vaccination - as the GR "survey" suggests - wouldn't it be nice to be able to "mine" the data for other possible connections? By looking for subjects based on their vaccination status, the only question that can be answered is whether there is a correlation between the two.


My Modest Proposal:

This is a study that could be done rather quickly and with a minimum of expense. It would eliminate many of the sources of bias and would fairly easily generate balanced study populations that would be a good match to most of the general population.

[a] Contact a large HMO with actual facilities (e.g. Humana or Kaiser) and arrange to get access to their patient medical records. This is routinely done, although the HMO will want assurances that patient confidentiality will be maintained.

[b] Obtain a list of patients with autism diagnosis in the proper age range (I would suggest 6 - 12 years).

[c] Select one thousand of these patients at random. This would allow you to detect a difference if the prevalence of unvaccinated children is less than 1/3 that in the general population (alpha error level 5%, beta error level 5%). If the difference is less than that, you'll need to select more subjects.

[d] Confirm the diagnosis by having a child psychiatrist or psychologist review the records.

[e] For each of the remaining children, select a non-autistic control child from the HMO database that is of the same age, sex, geographical region, etc.

[f] Determine how many of the children in each group have received all, none or some of their vaccinations (keep track of which vaccines, when, etc.). If the GR "survey" was right (a very big "if") about the number of children unvaccinated, each group should have around 30 unvaccinated children, unless there is a correlation between vaccination and autism.

[g] If the autism and non-autism groups have statistically significant differences in their vaccination rates, then a correlation can be claimed. If the study shows no correlation, then the relative risk is less than 3. You'd have to have twice as many subjects to bring the minimal relative risk to below 2.

Using HMO patients eliminates any issues of affordability (which is minimal) or access to health care. Although the population of people who have HMO coverage is not necessarily the same as the overal US population, using the case control design ensures that the two groups are as similar as possible.

This study could have been done in the time - and for the reported cost - of the GR "survey". If they had done a real study - like the one I've outlined above - the answer would already be here.

If anybody would like to fund such a study, please contact me. If I can't find anyone else to do it, I'd be willing to coordinate it myself.

I doubt that any of the federal funding agencies will be interested in funding this study - not because of any conspiracy, but because the only people who want the study will probably not believe the likely outcome (i.e. no association - just as in the GR "survey").

So, this is my challenge to those who want this study: if you want it, do it. The advocacy groups have the money - all they need to do is find the will to take a chance. And make no mistake - this is a risk. There is a better than even chance that the study - if it isn't "fudged" - will show no correlation.

If they really want to know, they can find out for less than the cost of a full-page ad.


Prometheus