Closing the evidence gap in integrative medicine

I have now looked up the references cited by John Heptonstall in his
response to David Colquhoun. Here are the results:

Reference 1 comprises anecdotal testimonials on the website of a
purveyor of Vega test machines.

Reference 2 is to a commercial website of a biofeedback machine
manufacturer. There are no primary research data.

Reference 3 is a 1997 RCT of Vega testing, which reports positive
results. No sample size calculation was reported, raising the possibility
of a type I error.

Reference 4 is an inconclusive study in dogs of a serological test
for food allergy. It is not about Vega testing.

Reference 5 is to a single subject study comparing various methods
for allergy testing. Vega testing did not do well against some other tests
such as IgG.

Reference 6 is library research on the recorded causes of food
allergy.

Reference 7 is to a cross-sectional survey on food intolerance. They
authors state: “There were no associations between the tests for food
allergy and malabsorption and perceived food intolerance.”

Of these seven references, only one is to a randomised double blind
clinical trial, but this is now 12 years old. I would have expected
Heptonstall to cite something that replicates these results. The
interesting truth is that there is a later study, but its authors
concluded: “Electrodermal testing cannot be used to diagnose environmental
allergies” (1). So Vega testing fails one of the cardinal scientific
tests, that of replication.

Heptonstall seems to have copied many references from one response to
another, but they are difficult to check and I may have missed some. I
would recommend that he uses conventional scientific notation for journal
citations rather than web addresses – they would be much easier to check.

1. Lewith GT, Kenyon JN, Broomfield J, Prescott P, Goddard J, Holgate
ST 2001. Is electrodermal testing as effective as skin prick tests for
diagnosing allergies? A double blind, randomised block design study.BMJ.
2001 Jan 20;322(7279):131-4.

Competing interests:
None declared