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Flashcards in unit 17 Deck (18):

Where did iridology originate from?

ridology originates from a ten-year-old boy’s observation in Hungary in 1836 that the iris of an owl with a broken leg had a single sharp black line that disappeared when the leg had healed.


What is the theory of iridology?

Iridology is based on the theory that by examining the iris (coloured portion of the eye) one can identify toxicity and inflammation in the connective tissue of the body. It is claimed that this unhealthy tissue is the predecessor to both physical and emotional disorders.


How does the iridologist use their information?

The iridologist will recommend particular herbs and other natural foods to prevent the diseases that the client is vulnerable to.


Who typically uses iridology?

Iridology is typically used by complementary medicine therapists, such as herbalists, who do not have access to, or training in, medical diagnostic tests.


How is iridology practiced?

Supporters of iridology claim that the body and its inner organs are projected onto the iris. Iridologists have created topographic maps of the iris that allow organ-specific diagnoses. However, the various topographic iris maps are not entirely consistent as to the representation of a given organ within the iris


What does iridology claim in regards to location of organs and eye? What does this facilitate?

As in ear acupuncture and reflexology, iridologists claim that all organs are connected to an easily accessible body part. It is as if human evolution was planned to facilitate the diagnosis and treatment of disease.


How are iridologists licensed?

Practitioners can obtain a certificate in iridology through a correspondence course. The practice of iridology is completely unregulated.


What do students learn in iridology courses?

Such courses claim that students learn how to identify inflammation, inherent body strengths and weaknesses, general health states, drug accumulations, nutritional deficiencies, prolapsed organs, poor circulation, tension, toxemia, and acidity levels using photographs.


What are the benefits to iridology?

There is no scientific evidence that iridology is beneficial as a diagnostic tool.


What are some contraindications to iridology?

Iridology is contraindicated for any condition that may be caused by underlying disease, or for patients with serious infections. Any condition that would create serious harm from delay in medical treatment should not be treated solely by an iridologist (e.g., cancer, ear infections in children). Other considerations are that contact lens wearers may have iris changes from lens wear, not from an internal imbalance, and that bright lights used in iridology diagnosis may irritate those with sensitive eyes. Finally, the time and cost of an iridology diagnosis may be prohibitive.


Describe how you might test in a clinical trial the effectiveness of iridology?

Clinical studies by Simon et al. (1979) compared the diagnoses of ophthalmologists and iridologists in examining photographs of the irises of 143 individuals, 48 of whom had known kidney disease as defined by elevated blood creatinine levels. The percentage of correct diagnoses was no better than could be expected by chance and there was no difference between the ophthalmologist and iridologist groups. In particular, the best screener correctly identified patients with kidney disease 57 per cent of the time and incorrectly identified patients with no kidney disease (type 2 error) 43 per cent of the time. Simon et al. (1979) concluded that iridology is of no value for the diagnosis of kidney disease.


What types of harm has research found iridology can produce?

Moreover, it may produce two types of harm: first, psychological harm as a result of people (wrongly) believing that they have kidney disease, and, second, kidney disease being present but undiagnosed and therefore untreated.


Describe how you could test an iridology hypothesis using slides?

In the case-control study described in the reading assignment, Knipschild (1988) had iridologists diagnose the presence of gallbladder stones from slide pictures of the right iris of a group of patients with confirmed gallbladder stones and a group of control subjects. Knipschild found that iridologists could not distinguish between cases and controls.


What did the german study of iridology find?

A study in Germany investigated whether iridology was of any value as a diagnostic tool in detecting cancer (Münstedt et al., 2005). The researchers enrolled 68 patients with types of cancer, and 42 control subjects. Each subject was examined by an iridologist who was then asked to suggest a diagnosis. However, his success rate was so low that the researchers concluded that “Iridology was of no value in diagnosing the cancers investigated in this study.”


Summarize iridology

From the research completed to date, it is fair to conclude that there is no scientific basis to iridology, there is no established connection between the eye and other body parts, and there could be adverse consequences due to misdiagnosis. In addition, natural variations in eye colour and pigmentation need to be taken into consideration.


What are the benefits and potential hazards of iridology?

There are no known benefits. The major potential hazards are misdiagnosis (false positives and false negatives).


Suggest how a carefully conducted clinical study could be carried out to determine the scientific effectiveness of iridology.

A study to determine the scientific validity of iridology would be as follows:
a. Select patients attending a specific medical clinic that have been diagnosed with a disease (e.g., cancer patients, patients with gastrointestinal disease); photograph their eyes.
b. Recruit age– and gender–matched healthy control patients without the disease; photograph their eyes.
c. Code and arrange the photographs/slides in a random fashion.
d. Have several iridologists who are blinded to the patients’ diagnoses attempt to diagnose the patients, based on the analysis of the photographs.
e. Analyse the results and compare the number of true positives and true negatives derived from iridology versus chance.


There is no scientific basis to iridology. (T or false)