Iridology and Credulity

The NZ Herald’s Life & Style section has (once again) affirmed their dedication to credulity, in an article by Donna McIntyre extolling the supposed virtues of iridology in what reads like an advertisement for a naturopath called Peter Riddering, ND (Not a Doctor) – Iridology: What the eyes reveal

EDIT: It seems the article has been moved into the NZ Herald’s Health & Wellbeing section (a subset of Life & Style): Iridology: What the eyes reveal

The article’s contents consist mostly of quoting Mr Riddering talking about how iridology supposedly works. No attempt is made, of course, to provide evidence supporting the claims he’s making. In fact, it seems the closest thing to supporting evidence that is offered is an argument from antiquity:

Modern iridology dates back to a Hungarian doctor Ignatz Peczely in the late 1800s but Peter says the Mayans, Egyptians, Chinese and Incas were also aware of iris markings and their link to health.

I’d like to flesh out the history of iridology a bit more than was done in the Herald article. The story goes that a young Ignatz Peczely observed a dark fleck in the iris of an owl with a broken leg (some reports claim that he broke its leg himself). After the owl had recovered, he noticed that the owl’s iris no longer contained the dark fleck, but instead contained a few white lines in about the same place.

When he had grown up, Peczely apparently became a homeopath (a sure sign of a quack if ever there was one). In his misguided attempts to treat people, he apparently noticed a similar fleck to the one he once observed in the owl in a man who, apparently, also had a fracture. After this, Peczely started to create a “map”, based on his observations, detailing how he thought the iris acted as a map of the entire body.

This “homunculus approach” to diagnosis, where one particular body part is believed to act as a map of the rest of the body, is relatively common in fake medicine. For example, tongue diagnosis is central to the practice of traditional Chinese medicine (TCM). Reflexology, which is essentially the idea that pretty much anything can be cured by a foot or hand massage, is another example.

Now let me just stop here. Nothing I have said so far really matters when it comes to whether or not iridology is a valid method of diagnosis. The things I have described are red flags, but they are far from conclusive. The real problem is what happened after Peczely’s original observations. Here’s what should have happened:

After making his initial observations, Peczely should have developed a hypothesis that internal medical problems can be diagnosed by examining the iris. In order to determine whether or not his hypothesis was true, he should have set up and carried out a set of rigorous tests that were capable of disproving his hypothesis.

That is not what happened.

As far as I can tell, iridology is based off “maps” that have been created not via rigorous testing of falsifiable hypotheses, but as a result of singular observations coupled with confirmation bias. Iridology is simply not supported by anatomy or physiology, and has never been shown to be an effective method of diagnosis or recognised as a legitimate diagnostic approach. Despite this, Peter Riddering charges people $65/hour for iridology sessions.

As he mentions in the Herald article (perhaps the only useful piece of information in there):

naturopaths are not allowed to make medical diagnoses. If [Mr Riddering] does come across anything, he suggests client go to their doctor

The way I see it, if you’re worried you might be ill here are 2 of your options:

  1. You see Peter Riddering, not a doctor, who uses a bogus method of diagnosis and, if he finds anything, tells you to see a real doctor.
  2. You see a real doctor.

I have to admit, I really don’t see the appeal in the first option. It seems the only differences are that the first option…

  • costs more
  • essentially funds fake medicine
  • carries a greater risk of misdiagnosis
  • takes more time

I’m not a medical doctor, so I’m going to give you the only health advice I’m qualified to give: ask a medical doctor

Here are some evaluations of iridology I found via a very quick search on Google Scholar, along with relevant excerpts from their abstracts:

  • An Evaluation of Iridology by Allie Simon; David M. Worthen, MD; Lt John A. Mitas, II, MC

    Iridology had no clinical or statistically significant ability to detect the presence of kidney disease. Iridology was neither selective nor specific, and the likelihood of correct detection was statistically no better than chance.

  • Iridology: Not Useful and Potentially Harmful by E. Ernst, MD, PhD, FRCP (Edin)

    In conclusion, few controlled studies with masked evaluation of diagnostic validity have been published. None have found any benefit from iridology. As iridology has the potential for causing personal and economic harm, patients and therapists should be discouraged from using it.

  • Iridology: A critical reveiw by Lennart Berggren

    [Controlled] clinical trials and experiments conclusively show that iridology has no ability to detect disorders in other parts of the body; there are sufficient proofs that iridology is purely conjectural. Iridology is of no medical value and might even be a potential danger to people seeking medical care. It should be exposed as a medical fraud.

  • Changing belief in iridology after an empirical study by P. Knipschild

    My paper on iridology presented evidence against its validity as a diagnostic aid.

    Note that this article itself did not assess the validity of iridology, but instead how doctors’ beliefs change when confronted with evidence against it.

  • Iridology: A Systematic Review by Ernst E

    Conclusion: The validity of iridology as a diagnostic tool is not supported by scientific evaluations. Patients and therapists should be discouraged from using this method.

  • An investigation of the relationship between anatomical features in the iris and systemic disease, with reference to iridology by PhD T.J. Buchanan, PhD C.J. Sutherland, PhD R.J. Strettle, PhD T.J. Terrell, MSc A. Pewsey

    The results demonstrate that the diagnosis of these diseases [ulcerative colitis, asthma, coronary heart disease or psoriasis] cannot be aided by an iridological style analysis.

  • Can Iridology Detect Susceptibility to Cancer? A Prospective Case-Controlled Study by Karsten Münstedt, Samer El-Safadi, Friedel Brück, Marek Zygmunt, Andreas Hackethal, and Hans-Rudolf Tinneberg

    Conclusion: Iridology was of no value in diagnosing the cancers investigated in this study.

If you’re at all worried that I’ve cherry picked the studies that support my conclusions, the quoted articles were simply all the links on the first page of results when searching for “iridology” on Google Scholar.

It seems iridology simply does not work. Anyone who says otherwise is either ignorant or dishonest.

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Entitlement and Religious Exemptions

What the New Zealand Herald Refuses to Understand

While driving to work today, I heard a news item about an employee of SkyCity, Tuni Parata, is facing some degree of disciplinary action after being found with a personal book on her. Apparently this is in breach of SkyCity uniform code, which does not allow employees in certain roles to carry personal items such as mobile phones or books. I was wondering why this was in the news, then it was mentioned that the item she was found with just happened to be a pocket Bible. Okay, I thought, that’s probably why it made the news, but no big deal.

Then, when having lunch, I saw this headline on the front page of the New Zealand Herald:

Thou shalt not…
casino bans Bible

I read the article to make sure I hadn’t misunderstood when I heard about the story on the radio in the morning, and two sections stuck out to me:

As a general principle, staff in customer service roles are in breach of SkyCity’s uniform standards if they carry items such as mobile phones, books and other items which might interfere with their customers.

Grainne Troute, SkyCity’s general manager of group services

a union rep told [Ms Parata] it didn’t matter if it was “a Playboy magazine or a Bible, it was not work-related material, therefore should not be with you front of house and certainly not being read”.

Perhaps whoever wrote the headline didn’t bother to read the entire article? Unfortunately, it seems more likely to me that this is indicative of the Herald prioritising getting more readers over accurately representing the truth. If there is anything indicative of bad reporting, it is having a higher priority than accurately representing the truth. This headline is misleading, implying that the fact that the specific object Ms Parata was found with was a Bible was somehow relevant.

The article is available online under the headline Casino worker faces action over Bible at work. I don’t know why the headline is different here, and although it’s a certain improvement on the misleading sensationalistic one used in the print version, it’s still fixated entirely on an arbitrary detail.

Society is overprotective of religion. Religious ideas escape the criticism to which other ideas are subjected in the name of “respecting the beliefs of others”. As a result, when a religious idea is treated just like any other idea (or, like here, when a religious book is treated just like any other book) some people are going to think that the issue is about religion, and attempt to explain the discrepancy from normal behaviour by some prejudice against religion specifically. That’s what this article seems to be trying to do, particularly with its headline.

However, as expressed in the quotes above, that’s not the case. The discrepancy is because religion is not being handled with kid gloves. This woman has been told she’s not allowed personal books at work, and that includes her personal religious book, whether it’s important to her or not. I like to call this being treated as an adult. Instead of treating this woman like a child in the name of “respecting her beliefs”, the organisation is respecting her by treating her like an adult. I applaud them for this, at least. People are more important than ideas – they deserve respect by default whereas ideas should always stand on their own merits.

In reading this story I am also reminded of events like pharmacists refusing to fill birth control prescriptions on religious grounds. I realise the scale is entirely different here, but at some level the concept is the same: there is a conflict between one’s job and one’s religion.

I’m going to practise as I preach now, and give Ms Parata the respect of applying the same standards to her religious ideas as I would to her secular ideas. According to the Herald article, she made this claim:

Ms Parata said that carrying a Bible was a vital part of her faith and relationship to God.

Just to emphasise how ridiculous this sounds when we’re not handling religious ideas with kid gloves, I’m going to swap out a couple of words for essentially equivalent ones that belong to a religion that is typically treated with the respect it deserves by non-adherents:

Ms Parata said that carrying a copy of The Gospel of the Flying Spaghetti Monster was a vital part of her faith and relationship to the Flying Spaghetti Monster.

I doubt, however, the Herald or the union would be acting so outraged if this were the case.

EDIT:

It looks like SkyCity is going to grant Ms Parata an exemption from this rule – she will be allowed to carry her pocket Bible with her at work. I understand how this might be seen as necessary from a PR perspective, but I withdraw my statement of support. By exempting her from this rule on religious grounds they are respecting her beliefs over her, and not treating her like an adult. They’re furthering religious hypocrisy and I certainly will not support that.

I also think it might be worth clarifying that I’m trying very hard to make no comment on whether or not I think the policy is a good one. Whether or not the policy should exist or be enforced in the first place is irrelevant to my discussion; it’s the hypocrisy I take issue with.

NZ Herald Not Even Trying Any More

Australian “psychic” Sue Bishop recently made the claim that “All children are psychic and they’re tuned in to their abilities now more than ever”, according to New Zealand Herald reporter Nicky Park, who also happened to somehow conclude that this is newsworthy.

Apparently it is not only worth reporting, but true as well. Instead of reporting the facts – an Australian woman who is either a successful con artist or in dire need of psychological help has said something horribly incorrect – this reporter decided to report what she said as fact. The Herald article is incessantly credulous, even going so far as to feature a section entitled “How to nurture a child’s psychic ability”. Have a read of it, if nothing else it’s easy to laugh at.

It seems to me that the Herald simply isn’t trying any more (on that note, were they ever? Perhaps before my time…). If this sort of gullible crap meets its standards, then its standards must be worthless. As I’ve said before and I’m sure I’ll say again, the New Zealand Herald isn’t a newspaper, it’s an entertainment magazine.

EDIT:

It seems that Nicky Park is not, in fact, just some newbie reporter who happened to get it horribly wrong and who will be appropriately dealt with. No, in fact she appears to be the editor of the New Zealand Herald’s entire Life & Style section. Just when I thought it wasn’t going to get any worse…