Cutting a frog's legs off does not make it deaf.

Story:
A researcher puts a frog on a table, the frog just sits there. The researcher then, with his mouth just inches away from the frog's head, yells at the top of his lungs: "JJJUUUUMMPP!" The startled frog jumps forward.

The researcher amputates one of the frog’s legs and repeats the test: "JJJUUUUMMPP!" The startled frog jumps forward.

The process is repeated with the same results until there is only one leg left, when the researcher yells "jump" the frog attempts to jump and hobbles forward.

The final leg is removed, "JJJUUUUMMPP!" but nothing happens. No movement from the frog. The researcher's boss comes and asks "What have you learned today?" to which he replies: "cutting a frog's legs off causes it to go deaf."

I used to work in cancer research and was given this example of false positives. I'm posting this because it seems that despite how knowledgeable you are or how long "you've been in the business", even the best people readily accept things that they cannot explain simply because the symptoms can no longer be seen or felt.

ACS :: Glossary Search: "false negative: test result implying a condition does not exist when in fact it does.
false positive: test result implying a condition exists when in fact it does not."