Electro Physiological Feedback Xrroid (EPFX) (/ˈzɪərɔɪd/),[1] also known as Quantum Xrroid Consciousness Interface (QXCI), is a radionics[2] device which claims to read the body's reactivity to various frequencies and then send back other frequencies to make changes in the body.
[1][3] It is manufactured and marketed by self-styled "Professor Bill Nelson," also known as Desiré Dubounet.
[1] She is currently operating in Hungary, a fugitive from the US following indictment on fraud charges connected to EPFX.
[3] Descriptions of the device in mainstream media note its US$20,000 price tag and the improbable nature of the claims made for it.
In one documented case, undiagnosed and untreated leukaemia resulted in the death of a patient.