The real false positive rate for this test is not known yet.

FORBES: More On Why New York Times Story On Alzheimer's Test Was Overblown

If one in 1, 000 people have a disease and the false-positive rate for a test is 5%, then the probability that a person testing positive has the disease is at most 2%.

ECONOMIST: Letters | The

Fido can pick up the smell of TNTvapor at concentrations of just a few parts per trillion, and it was the first sensor to find buried mines at a level comparable to dog performance, with a false-alarm rate of less than 5%.

FORBES: A Nose For Bombs

But RSA, the security division of EMC, says 220 companies, including Target, Sears, Macy's, Sprint, T-Mobile and 14 of the 20 largest U.S. financial institutions, use its "knowledge-based authentication" (KBA) service and that it has a "false failure" rate (meaning folks flunking on erroneous public info) of less than 5%.

FORBES: Magazine Article

Now, a new studypublished in the Archives of Internal Medicine finds that the rate of false-positive activations is higher than expected.

FORBES: All Dressed Up And No Place To Go: False-Positive Activation Of The Cath Lab For Primary PCI

The rate of false alarms was significantly lower than that of competing systems, and when the system was presented with simulated attacks, it detected all of the common security breaches it was tested against.

ECONOMIST: A thousand ills require a thousand cures

It raided Lo-Rate's premises and confiscated damning evidence of false sales calls.

BBC: Person making a phone call

Past efforts to cut hospital queues have been based on the false assumption that they are a simple backlog, and that increasing the rate of treatments will eventually clear the backlog.

ECONOMIST: Waiting for Dobbo