The veteran is informed of the results of the examination during a personal interview and gets a follow-up letter further describing the findings. Each veteran is given the opportunity to ask for an explanation and device where medically necessary, a follow-up examination or additional laboratory tests are scheduled. The examination and tests sometime reveal previously undetected medical problems. These discoveries permit veterans to get prompt treatment for their illnesses. Some veterans think they are in good health, but are worried that exposure to Agent Orange and other substances may have caused some hidden illness. The knowledge that a complete medical examination does not show any medical problems can be very reassuring or helpful to Registry participants. All examination and test results are kept in the veteran's permanent medical record. This information is also entered into the computerized VA Agent Orange Registry. So far, more than 375,000 Vietnam veterans have participated in this program. For more information about the VA Agent Orange Registry, see Agent Orange Brief, B1.