A comprehensive overview of these "electrodiagnostic devices" can be found at quackwatch.org Most medical practitioners view the machine and their proponents as dangerous, due to the danger of misdiagnosis. Another concern is that individuals under treatment by VEGA practitioners will forgo assessment or treatment by medical doctors, thereby delaying or eliminating accurate diagnosis of their condition. One commonly-cited case involved a single pregnant woman who was diagnosed with cancer, and had a history of depression. The woman sought a second opinion, and found a vega machine. The operator told her she was not pregnant, and did not have cancer, that instead she was eating too much white flour. She stopped eating bread and anything else with flour in it. She eventually gave birth with a midwife in her home. The baby had suffered from a lack of folic acid, which the government adds to flour to ensure that all pregnant women get enough in their diet. In addition, her cancer spread, and she died about a year after her child's birth. The inquest concluded that the woman had suffered from a recurrence of depression, and that her child was born with a neural tube defect that was at least partially caused by the vega machine's operator telling her fictional information. Proponents of Vega machines claim that this is an isolated case that arose from a lack of regulation and an unqualified operator, and that it is not sufficient to dismiss the device. Similar incidents have occurred with the use of other Electrodiagnostic devices, in this case a MORA machine.
Proponents of the device contend that the skill of the operator is critical in a correct assessment of ailments or general health, and commonly use this statement to counter specific criticism and validate the device. Opponents contend that these devices are little more than fancy galvanometers that measure electrical resistance of the patient's skin. They point to the fact that the size of the number the device reads out in testing actually depends on how hard the probe is pressed against the patient's skin. They also note that moving the glass ampule to various wells in the honeycomb has no effect on readings with the probe against parts of the hand (the person manipulating the vial was not the same one that held the active probe in this testing). They conclude that this is consistent with expectations, given that the honeycomb is made from a solid block of metal, and especially since the ampule is made of glass, an electrically nonconducting material. Proponents generally counter specific claims by stating that these machines use principles outside the conventional understanding of science, such as "resonances" and "energy balances", and make broad and unsupported claims as to the efficacy of the Vega. Opponents say these mystical statements are simply unsubstantiated, convoluted pseudoscientific jargon,and offer as one example the following sentence taken from the handbook which accompanies the Vega machine: "Only after applying a suitable stress, which forces the organism to regulate in response to this stress, can the energetic compensatory processes be made manifest for a short time, and in most cases, show a clear correspondence with the morphological findings."