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When you compare CEDS with regular medical testing, you must be aware of the accuracy of those tests. Some are not very reliable.

Cytotoxic Testing

"The cytotoxic test gives immediate, objective results, and detects masked sensitivities. However, it is expensive and will sometimes show a false negative result if the food has not been eaten for several months. The skill of the person reading the slides also affects its accuracy. Cytotoxic testing has been found to be very accurate for some people, while less so for others." - page 54-55

Allergy Relief & Prevention by Jacqueline Krohn, MD

Provocative Neutralization Testing

"...Vivid symptoms produced help to convince the more reluctant that the test substance is indeed a problem. While some of these symptoms are uncomfortable, even children do well with this method of testing. It is, however, a time-consuming process, and only a few substances can be tested during each session. - page 57

Allergy Relief & Prevention by Jacqueline Krohn, MD

RAST, MAST, and ELISA tests

"...RAST tests misses out on more than fifty percent of allergies." - page 237

from The Canary and Chronic Fatigue by Majid Ali, M.D. 1994

"The RAST, MAST, and ELISA tests all have false-positive and false-negative results." - page 29

The Rebellious Body, Reclaim Your Life from Environmental Illness or Chronic Fatigue Syndrome by Janice Strubbe Wittenberg, R.N.

Serial Dilution Endpoint Titration

"...This method is very accurate for testing inhalants in those individuals with high IgE levels. However, results for food and chemical allergies tested by this method are not accurate. - page 56

Allergy Relief & Prevention by Jacqueline Krohn, MD

Skin Prick Test

[While searching I found this article, which is quoted often on the unreliability of CEDS. It brought back a memory of mine. When the RAST test was new, I asked the local ear-nose-throat expert doctor about it. He said it was no good. Two years later I got tested at his office using the RAST test.-bfg]

"Electrodermal testing measures electric impedance on an acupuncture point and is a common form of unconventional testing for allergies. In a double blind, randomised block design study, Lewith et al (p 131) evaluated how it compared with conventional skin prick testing in 30 volunteers. Half of them had reacted positively to a previous skin prick test for allergy to cat dander or house dust mite. The results of more than 1500 separate allergy tests showed that electrodermal testing does not correlate with skin prick testing and so should not be used to diagnose these allergies." [Conclusion was interesting in that the prick skin test is not to be used for diagnosis without a detailed patient history AND it isn't all that accurate (see below).  Also, EDS is a screening device. The doctor does the diagnosing not the device.-bfg]

The study assumed skin prick testing was 100% accurate. I would have believed the study if and only if the allergies were ones that the patients verified. I searched the internet and found these references to the skin prick test:

"But the accuracy of the skin prick test can range from 30 to 63 percent, Szeinbach said."

Ohio State University Research

"...However, if IgE levels are low, there may not be a wheal - indicating an allergy - even if the person tested is sensitive to these inhalants....Since over 85 percent of food allergy is non-IgE mediated, this type of testing cannot give an accurate picture of a person's food problems. The scratch test also cannot be used for testing chemicals, since most chemical reactions are not IgE mediated." - page 55

Allergy Relief & Prevention by Jacqueline Krohn, MD

"The prick skin test is simple, rapid to perform, highly sensitive and cheap. It is only semi- quantitative and unless controlled carefully can yield false positive or false negative results. It must be kept in mind that positive skin test indicates the presence of IgE antibody but this by itself does not mean that the individual has an allergic disease. The prick test has largely replaced the scratch test as it is less invasive and gives fewer false positives. The intradermal test is more sensitive but yields more false positives"

[dead link from 2008]

"Now most doctors reckon that an accurate medical history contributes 80% of the diagnosis, and testing the other 20%; and yet patients often think, or would like to believe, it’s the other way round: which may be true in some branches of medicine but it is certainly not true in allergy at the moment.

"We would certainly like an accurate test for food allergy. The skin prick tests (SPTs) that I mentioned earlier are a very accurate test but only unfortunately for acute types of allergy that include foods such as nuts, eggs, and fish, for example. In practice we have found quite a lot of patients allergic to potatoes by this method and cutting them out has proved effective in relieving symptoms. Unfortunately though if eczema is associated with a food it is often not an acute reaction but rather a delayed one and delayed reactions will not give positive SPTs.

Blood tests are no better either: the so called RAST (CAP) tests are similar and less accurate than SPTs. IgG4 tests available only privately maybe more helpful but give many false positive results- more trials looking into their value are being planned.

"It is impossible to accurately demonstrate intolerances through conventional testing methods."

"As is the case with skin tests, a direct correlation cannot be assumed between evidence of allergen-specific IgE antibody and clinical disease. Therefore, the interpretation of these results by the physician requires correlation with the history and physical "examination obtained by face-to-face contact with the patient."
from: Annals of Allergy, Asthma, & Immunology. Volume 75 (6), December 1995.

"Prick testing is used for diagnosis of clinically immediate (IgE-mediated) hypersensitivity induced by a wide variety of inhalant and food allergens. Performing and interpreting skin tests require training and practice. It is virtually impossible to quantify the exact amount of injected material used in prick tests. Therefore, the reliability of the test depends on the device used, the depth and force of the puncture needle, the duration of force, the angle of the application device, and the stability of extracts."

"Intradermal tests are used when prick testing is not sensitive enough to detect the cause of an allergic reaction."

"In general, intradermal and prick tests are safe. Possible complications include large local reactions and, rarely, immediate systemic reactions. The latter are more common with intradermal tests because the absorption rate is much higher than in prick tests. The rare fatalities attributed to skin testing have all occurred after intradermal procedures; no deaths have been reported after prick testing."

Gerald W. Volcheck, MD

" Unfortunately, the standardized test reagents available in Europe with known protein and antigen content are still not commercially available in the United States. "

Parents and children were told and the children recorded in their booklet which allergens caused a reaction on their arm. In addition, they were given a note explaining that a reaction does not necessarily mean that an allergy to that substance was present, and that if there was no physical reaction to exposure then no action needed to be taken.

Skin tests are used to prove sensitization. A skin test is only valid when the result is positive. Negative skin tests do not exclude allergy. The skin tests are scanty in reliability and not useful in nonimmunological drug reactions.
Environ Dermatol 5 : Suppl 2 : 68-73, 1998

Limitations False-positives: nonspecific irritant reactions; dermographism interpreted as a wheal; hemorrhage at prick site interpreted as erythema; allergen spread from one site to another when the same needle is reused; small wheals (eg, 2 mm) interpreted as significant; impurities or contaminants in allergen preparations; test sites improperly spaced; inappropriate allergen concentrations

False-negatives: waning potency of allergens; inadequate concentration of allergen; technical errors in epidermal puncture; drugs such as HI antagonists, hydroxyzine, tricyclic antidepressants, phenothiazines, dopamine; skin diseases such as atopic dermatitis; possibly extremes of age

"Skin prick test: Most people are familiar with allergy skin prick testing (SPT). A positive latex SPT is a sensitive indicator of an IgE sensitization. There is as yet no FDA-approved latex extract available for skin testing in the United States. Dr. Robert Hamilton at the Johns Hopkins University is leading a study of a latex extract for SPT use. The clinical trials are in the final stages, and FDA approval of an extract is expected by the end of 1998. Pending this outcome, some physicians are making their own extracts. Typically, they do this by cutting a latex glove into pieces and soaking them in saline for t5 minutes, thereby producing a viable extract. A positive reaction is considered proof of a type I latex allergy. This sort of testing is not recommended for a person who has already experienced a severe type I or anaphylactic reaction to latex. Appropriate emergency equipment must be available if a latex SPT is done."

"Skin tests are of lower efficacy in the assessment of the response to low molecular weight antigens because many of these must be conjugated to other proteins, may act as skin irritants, and thus have higher rates of false negativity and of false positivity, if not prepared and applied by experienced personnel.
"Given the present state of the art of immunologic testing for occupational asthma, such testing should be reserved for investigative purposes, principally."

Allergy skin tests detect only the presence of antibodies. They cannot make an accurate determination that an allergy exists.

The least expensive allergy skin test is the skin prick or puncture test.

Allergy skin tests are cheap and easy to do. However, the predictive value of these types of tests varies depending on the patient's allergy history. For example, it is not uncommon for patients with a strong history of food allergies to have negative skin tests or weakly positive skin tests to specific foods that they know cause problems. [If a food has been avoided for quite some time, the body does not react as strongly, either - bfg] In general, up to 50 percent of sensitive allergy patients will have a false negative reaction. Up to 15 percent of patients with low sensitivity to the allergen will have a false negative reaction." - pg 101

The Complete Idiot's Guide to Food Allergies by Lee H. Freude, M.D., and Jeanne Rejaunier, Penguin Group, 2003


Food intolerance is different from food allergy there is a huge difference.


The information contained herein is intended for educational purposes only.

BE AWARE: The electrodermal testing devices have not been approved by the Food and Drug Administration ("FDA") for assessment of nutritional deficiencies, food allergies, the presence of toxins, Candida, Epstein Barr virus, or the weakness of organs and glands. Use of the device for these purposes is inconsistent with FDA approval. The galvanic skin response device  is a Class II device that may be used for lie detection and for biofeedback.

There are no generally accepted completed clinical studies which demonstrate that the electrodermal testing devices are effective when used to assess for nutritional deficiencies, the presence of toxins, food allergies, Candida, Epstein Barr virus, and the strength or weakness of organs and glands.

Your child's exposure to lead or heavy metals cannot be determined solely through electrodermal testing.

You should not make decisions about your or your child's health and nutritional needs from information obtained solely through electrodermal testing.

You are to discuss all CEDS recommendations with your health care provider before implementing any of them.

There are medical tests for many, if not all of the issues that  respondents use electrodermal testing to assess, and  you are strongly encouraged to confirm the exposures identified through standard medical testing if you or your family physician feel that it is necessary.

Laws regarding this equipment vary from country to country.