There are lots of diagnostic tests available outside of the conventional medical system and those include tests for food intolerance, like vega testing, kinesiology, hair "body field analysis" testing, cytotoxic and live blood testing. 

Doctors and medical practitioners can be justified in assuming the worst and dismissing test results that originate from services such as 'mail order laboratory testing services', as there is no way for them to distinguish between those results which have an evidence basis with clinical data and those that claim results without any real evidence. 

 Consumers absolutely should be able to take more responsibility for their health, and have access to tests that can empower them, but society has to try to make sure they are protected from hucksters selling tests results or products that can potentially damage them.  In a world where alternative medicine marketing tells people that regular medicine is too conservative and corporate, how can individuals tell the difference between the good and the bad among the plethora of diagnostic tests that are available to them, and which are based on good science and those that have no basis in science?

Food intolerance is big business these days.  People in wealthy, developed nations have the luxury of better diagnosis and sometimes people who just want the attention of claiming a disorder. But for everyone else, mail order tests can be helpful. In order to show that results from a specific diagnostic test are meaningful, and can be interpreted and acted upon accurately and effectively, it is absolutely essential that food intolerance tests undergo rigorous evaluation to make sure that they perform well enough to provide accurate and reproducible information. 

 For the first time, some guidance has been issued to help people ask the right questions of diagnostic test providers, and it is coming from the inside of the industry. 

 The checklist published in Nutrition Practitioner, includes:

- Check that the test is accurate (what evidence exists?); has the test been referenced or calibrated against a recognized international standard? If no 'gold standard' reference point exists then clinical studies to show effectiveness must be provided. 

- Look out for real case studies and testimonials to show that the test works in practice, and can be interpreted correctly. Talk to other people that have used the test and find out about their experience.

- Check that the supplier has evidence that the sample (for example a blood sample) is stable during transport to the laboratory. Also ask for the supplier to provide reproducibility data.

 - Check whether the test supplier is audited annually by the UK Health Authority (the MHRA), is CPA (Clinical Pathology Accredited) or accredited in its country. Also ensure that the tests and sample collection methods have been CE marked, in Europe. The supplier should be able to provide their certificates.  

The checklist has been welcomed by food intolerance test suppliers YorkTest Laboratories. Dr Gill Hart, Scientific Director at YorkTest Laboratories commented, saying, "The food intolerance testing industry has been given a bad name by suppliers of tests that have absolutely no basis in science. YorkTest have been offering food intolerance testing services for over 30 years and have helped many thousands of people over the years. Our clinical data speaks for itself and we are pleased to now see measures being put in place that can distinguish our services from those that do not meet the criteria on the checklist. 

 "Being able to question the suppliers of diagnostic tests will help people to feel confident to really tackle their food intolerance symptoms, knowing that their targeted action is based on good sound information." 

YorkTest Laboratories, for example, has a  finger-prick home-to-laboratory food and drink intolerance test that measures IgG antibody reactions to 158 foods and also ingredients found in beverages.