A number of experts and the Centers for Disease Control have suggested that all patients admitted to chemical dependency facilities should be tested for the presence of the HIV antibody. It is reasoned that if people with positive tests knew they were infectious, they would practice safe sex and avoid needle sharing, however, there is little data to support the notion that knowledge of HIV antibody status alters these practices. There are clear social costs to pay for being HIV positive, such as denial of insurance and job discrimination. With little to gain and so much to lose, one must use caution in recommending to a patient to take the test. 13 notes.