The FSM recommendations for pathology tests are based on the following four principles:
Does the test result reflect the reality in the patient's body? In other words, does the measurement in the test tube accurately reflect the measurement in the patient's blood (or whatever tissue is being analysed)? This characteristic of the test is called its "analytical validity".
Does the test result have a significant relationship with the disease in question? In other words, is the measurement typically abnormal in patients with a particular disease? Can the test result be used to predict that a person is likely to develop a particular disease? This characteristic of the test is called its "clinical validity".
Does the test result provide additional information that is not already available? In other words, does the test result enable the patient to make a health care decision that would not have been otherwise possible? If the test result simply confirms something that the patient already knows, then the test has not provided useful information. This characteristic of the test is called its "clinical utility".
Is the test cost-effective? Is the cost of the test justified by its usefulness? This is important for both governments and individuals when they decide for what tests they will pay.
In Australia most pathology services are provided by NATA-accredited laboratories in either public hospitals or by private pathology organisations. However there is nothing to prevent non-accredited laboratories offering non-validated tests that do not meet the above four criteria and even accredited laboratories offering non-validated tests. However non-validated tests will not be covered by a Medicare benefit. This criterion alone is not sufficient to discriminate between validated and non-validated test however, as there are a number of tests that do meet the above criteria for particular patients but are not covered by Medicare. These tests include some new tests not yet assessed for the Medicare Benefits Schedule, some tests used for very rare diseases and many new genetic tests. Users may have to pay the full price from their own pocket or in some cases State Health Departments will cover the cost.
In order to assist Australians to make informed decisions about their own healthcare Lab Tests Online has established a list of Unvalidated Tests and included a link to the list from this title in our TEST drop-down list. Unvalidated tests will also be searchable using the SEARCH box in the centre of each page.
Initially the list will consist mainly of those laboratory tests identified by the Friends of Science in Medicine report and also those identified by the Australasian Society for Clinical Immunology and Allergy. However we will continuously update the list as we become aware of further items that should be included.
We at Lab Tests Online understand that Australians have the right to have whatever tests they want as long as they are prepared to pay for them themselves. Our aim is to assist in decision making and point out some of the pitfalls:
To go to a more complete discussion of laboratory test validation, use and interpretation click HERE
Below is our current list of unvalidated laboratory tests. If you have suggestions to add to this list please send them to us via the Contact Us form.
You can also see a list that includes non-laboratory tests at the US-based site: Quackwatch – Dubious Diagnostic Tests
FSM = Friends of Science in Medicine ASCIA = Australasian Society for Clinical Immunology and Allergy
Live blood analysis
Click on the links below for information on Live blood analysis:
Reverse T3 or rT3
Reverse T3 is an inactive form of thyroid hormone that is formed as a by-product during thyroid hormone metabolism. Reverse T3 levels will rise in very sick people e.g. those in intensive care. Knowing a person’s reverse T3 level has no clinical utility as it will not affect clinical decision making thus the test is not useful.
RCPA position statement on thyroid function testing.
UCDavis Health Blog
Salivary hormone tests
Salivary cortisol [late-night sample] for diagnosis of Cushing's syndrome has been found to be a valid and useful test. However, all other salivary hormone tests for reproductive hormones, thyroid disease, Addison's disease and other disorders of cortisol, melatonin etc., have not
been established as valid investigations.
"Functional" pathology tests
This is a large and complex area covering a range of tests e.g.:
- Liver Detoxification Profile
- Complete Digestion Analysis (also described separately)
- Intestinal Permeability
- Amino Acid Profile
- Organic Acid Profile
- Neuroendocrine Metabolites
- Essential Fatty Acids
- Vitamins and Antioxidants
The Liver Detoxification Profile
can vary from different laboratories. However most commonly it involves the person taking several common drugs e.g. paracetamol, aspirin and caffeine and then measuring their metabolites in blood and urine afterwards. The amount and ratios of metabolites present are an indication of the amount of phase I and phase II metabolism going on in the liver. However there is a lack of evidence that the results have any clinical utility in patients who are not suffering from advanced liver disease. The results are sometimes used by alternative practitioners to suggest that the patient has problems that are unrelated to liver function. People having this test may then be recommended to undertake “detoxification” treatment which as this WebMD article
shows, may be beneficial if the person leads a healthier lifestyle but this has nothing to do with removal of any "toxins".
Intestinal permeability testing
is usually used to diagnose “leaky gut syndrome”. Increased intestinal permeability can occur in a variety of severe gastrointestinal disorders but this is not what is meant by “leaky gut syndrome” in alternative and fringe practice. Read the article by the UK National Health Service in NHS Choices
for an unbiased assessment. Quackwatch
has included "leaky gut syndrome" in a list of "fad" diagnoses.
For more information on the above two tests click HERE
for an opinion by an Australian gastroenterologist.
Some of these “functional” tests have clinically valid uses in particular circumstances e.g. inborn errors of metabolism in very sick newborns and infants (organic acids, amino acids, fatty acids). In these cases the abnormalities are generally extreme and when combined with the clinical findings in the child the diagnosis can be made. However there is no good evidence that any of these tests are useful in the general population with vague symptoms. However it is common for an alternative health website to say something like; “Are you feeling unwell or tired and your doctor can’t find anything wrong with you? Come and have our range of functional health testing and we may find something wrong that will allow us to identify treatment options for you”. What do you think is going to happen when a large set of numbers are generated by the testing, normal variations due to diet and other factors are poorly defined and agreed protocols to interpret the results are non-existent? You will almost certainly be opening your purse or your wallet again to pay for more services.
Clot retraction tests
There is no evidence that this test is of any use. See also:
Complete digestive stool analysis
Analysis of stool for a number of substances can be useful in medical practice. The test used by mainstream medical practitioners, especially gastroenterologists, is described in this WebMD article
. However the Complete Digestive Stool Analysis discussed here includes a number of other items for which there is little or no evidence that they add clinical utility to the test profile. What they do add is extra cost and extra leeway to make non-scientific interpretations of the results if the practitioner so desires.
Hair analysis for toxins, mineral analysis (non forensic)
From the ASCIA assessment:
Method: Trace elements are measured from samples of hair, and nutritional deficiencies or excesses are related to the patient's symptoms.
Evidence: No evidence
Comment: While hair analysis is employed for toxicological/forensic use, there is no evidence that vitamin or mineral analysis from hair samples is useful for diagnosing disease or that treatment based on its results has any clinical utility. Blinded studies have shown variable and non-reproducible results from the same samples sent to the same and different laboratories.
Blood type testing for blood type dieting
Experts agree that while there is little harm in this diet apart from the inconvenience that it causes in selecting foods, there is no scientific evidence that there is any relationship at all between blood type and dietary needs or preferences.
Unvalidated cancer markers
Beware of unvalidated cancer marker tests. There are very few reliable blood or urine tests that provide early indication of the presence of cancer of any kind. For more information please read our article on Tumour Markers
See AMAS test following.
AMAS is one example of an unvalidated cancer test. Anti-malignin antibody in serum (AMAS) is a test offered by only one laboratory in the USA. While it is described by its manufacturer as useful in early diagnosis for those at high risk for cancer and in monitoring cancer progression, there is little published evidence from independent sources to support this claim. Despite more than 20 years of availability, the test has not earned the confidence of most in the medical community given the lack of data regarding its clinical utility.
The AMAS test is not specific to one particular type of cancer, which brings into question the test's impact on patient health outcomes. In other words, it is unclear how the test's results can be used to advance a diagnosis or develop a treatment plan for a patient.
The AMAS test, if used, should never be used alone to diagnose cancer nor to screen asymptomatic people for cancer. The available evidence indicates that a negative AMAS test should never be interpreted as an "all-clear" message if there is any other reason to suspect the possibility of cancer.
(also known as Bryans' or ALCAT testing)
From the ASCIA website:
Use: Diagnosis of food sensitivity / allergy.
Method: A suspension of patient white cells is incubated with dried food extracts on a microscope slide. Changes in the appearance and movement of cells are interpreted as representing a sensitivity or “allergy” to that food. The ALCAT test is a variation, whereby a mixture of blood and food extracts is analysed in an automated Coulter counter (cell counter).
Comment: These results have been shown to not be reproducible, give different results when duplicate samples are analysed blindly, don’t correlate with those from conventional testing, and “diagnose” food hypersensitivity in subjects with conditions where food allergy is not considered to play a pathogenic role.
Inappropriate use of conventional testing
Inappropriate use of conventional testing: Food specific IgG, IgG4, Food specific IgE (RAST, ImmunoCap testing), Lymphocyte subset analysis.
From the ASCIA website:
Food specific IgG, IgG4
Use: Diagnosis of food sensitivity / allergy.
Method: Antibodies to food are measured using standard laboratory techniques.
Comment: IgG antibodies to food are commonly detectable in healthy adult patients and children, independent of the presence of absence of food-related symptoms. There is no credible evidence that measuring IgG antibodies is useful for diagnosing food allergy or intolerance, nor that IgG antibodies cause symptoms. In fact, IgG antibodies reflect exposure to allergen but not the presence of disease. The exception is that gliadin IgG antibodies are sometimes useful in monitoring adherence to a gluten-free diet patients with histologically confirmed coeliac disease. Otherwise, inappropriate use of food allergy testing (or misinterpretation of results) in patients with inhalant allergy, for example, may lead to inappropriate and unnecessary dietary restrictions, with particular nutritional implications in children. Despite studies showing the uselessness of this technique, it continues to be promoted in the community, even for diagnosing disorders for which no evidence of immune system involvement exists.
Food specific IgE (RAST, ImmunoCap testing)
Use: Diagnosis of food sensitivity / allergy.
Method: Antibodies to food are measured using standard laboratory techniques. Some laboratories may present data inappropriately as raw counts or as “response factors”.
Comment: Inappropriate use may be divided into three areas:
(1) Inappropriate patient selection. As with any diagnostic test, use in patients where there is no evidence that food allergy plays a role in pathogenesis increases the likelihood of irrelevant false positive results. Use of food allergy testing in patients with inhalant allergy, for example, may lead to inappropriate and unnecessary dietary restrictions, with particular nutritional implications in children.
(2) Misinterpretation of results. Low levels of food-reactive IgE are found in some healthy individuals without clinical reactivity. Challenge studies have shown a correlation between allergen-specific IgE and then likelihood of reactivity to some (such as cows milk, egg and peanut) but not all foods. In the absence of a history of clinical reactivity, low levels of allergen-specific IgE are usually of little diagnostic significance.
(3) Inappropriate data presentation. Presentation of data as “raw counts” has no scientific or clinical rationale, has not been shown to correlate with clinical reactivity and renders results more liable to misinterpretation.
Lymphocyte subset analysis
Use: Conventionally used for the assessment of patients with suspected immunodeficiency or lymphoid malignancy. Also used by some unorthodox practitioners to assess patients with suspected “chemical sensitivity”, chronic fatigue syndrome or “environmental allergies”.
Method: Lymphocyte subsets are measured using standard laboratory techniques.
Comment: Lymphocytes in the blood are in transit between the various lymphoid organs and tissues where they perform their functions. Their numbers and proportions in the blood vary from day to day and are influenced by a wide range of physiological and pathological factors, including: time of collection, exercise, pregnancy, cigarette smoking, alcohol, medications, allergen exposure, infection and the presence of a variety of chronic disease states, including anxiety and depression. Misinterpretation of minor changes in the absence of evidence of immune deficiency or malignancy can be very misleading and may reinforce a patient’s concern that they are suffering from an immune disorder. This commonly occurs when the distinction between concepts of “energy” and “immunity” are blurred, and when health professionals offer ill-informed and unsubstantiated opinions about “immune dysfunction”.
This is a discredited test used by naturopaths and orthomolecular psychiatry practitioners. Excessive pyrrole excretion in the urine was originally claimed to be causative and diagnostic of a specific form of schizophrenic porphyria. Later practitioners have claimed without evidence that disordered porphyrin metabolism underlies a host of other conditions that are separate from the well-understood group of genetic and occasionally acquired diseases called the porphyrias.
The articles below discuss the so-called pyrolurias and the evidence against their existence.