The annual tradition of using Punxsutawney Phil to predict the weather on Groundhog Day has only been accurate 39% of the time since 1887, according to the Stormfax Weather Almanac. Weather Underground meteorologist Tim Roche says this is worse than a climate forecast, but experienced meteorologists are often wrong too. Groundhog Day dates back to […]
The accuracy of a pregnancy test after a miscarriage depends on hormone levels, timing, and the type of test used. Over-the-counter tests may be less accurate than repeat blood tests, which show hormone levels and changes over time. False positives are common, especially if the test is done shortly after the miscarriage. The accuracy of […]
PCR testing for HIV is accurate but requires trained professionals to read results. Antibody tests are commonly used and reliable after three months. PCR tests are expensive and not routinely used except for infants born to HIV-positive mothers. The polymerase chain reaction (PCR) test used to detect human immunodeficiency virus (HIV) is generally considered to […]
Genetic paternity testing is highly accurate, with two types of tests: an exclusion test to determine if a man could be the father, and an inclusive test to determine if he is. The inclusive test is usually over 99% accurate, but there is always some margin of error. Mothers can also be tested to increase […]
