Category Archives: The Numbers

HIGH FREQUENCY OF FALSE POSITIVE RESULTS IN HIV SCREENING IN BLOOD BANKS

RTB: What is an “hiv test”? A test that is only considered accurate for persons for whom they’re considered to be accurate…That is, they are a test for no one particular thing – but they are subjected to a social bias.

“[B]efore we screen low-risk groups for antibody to the human immunodeficiency virus (HIV), we should consider what the results would mean. Serologic tests for HIV antibodies appear to be characterized by extra-ordinarily high false – positive results in a low risk screening setting of voluntary blood donation.

“Furthermore, any increase in false positive rate could turn a screening program into a social catastrophe. A false positive result may label an infant, born to HIV positive mother, as HIV positive where as the same infant may actually be HIV negative.2
The false positive result regarding HIV in a neonate can lead to very serious problems.”

“If we want to test each other, we should make a deliberate choice of the threshold probability of infection above which we will screen. We should make explicit the trade-offs implicit in any testing program. How many engagements should end to prevent one infection? How many jobs should be lost? How many insurance policies should be cancelled or denied? How many fetuses should be aborted and how many couples should remain childless to avert the birth of one child with AIDS?” Continue reading HIGH FREQUENCY OF FALSE POSITIVE RESULTS IN HIV SCREENING IN BLOOD BANKS

Knowing is Beautiful – The Hidden Face of HIV – Part 1

GNN, Accuracy in Media and “Tutto in Vendita
February, 2005
by Liam Scheff

Read as PDF

As a journalist who writes about AIDS, I am endlessly amazed by the difference between the public and the private face of HIV; between what the public is told and what’s explained in the medical literature. The public face of HIV is well-known: HIV is a sexually transmitted virus that particularly preys on gay men, African Americans, drug users, and just about all of Africa, although we’re all at risk. We’re encouraged to be tested, because, as the MTV ads say, “knowing is beautiful.” We also know that AIDS drugs are all that’s stopping the entire African continent from falling into the sea.

The medical literature spells it out differently – quite differently. The journals that review HIV tests, drugs and patients, as well as the instructional material from medical schools, the Centers for Disease Control (CDC) and HIV test manufacturers will agree with the public perception in the large print. But when you get past the titles, they’ll tell you, unabashedly, that HIV tests are not standardized; that they’re arbitrarily interpreted; that HIV is not required for AIDS; and finally, that the term HIV does not describe a single entity, but instead describes a collection of non-specific, cross-reactive cellular material.

That’s quite a difference.

Continue reading Knowing is Beautiful – The Hidden Face of HIV – Part 1