ⓘ Triple test

                                     

ⓘ Triple test

The triple test, also called triple screen, the Kettering test or the Barts test, is an investigation performed during pregnancy in the second trimester to classify a patient as either high-risk or low-risk for chromosomal abnormalities.

The term "multiple-marker screening test" is sometimes used instead. This term can encompass the "double test" and "quadruple test" described below.

The triple screen measures serum levels of AFP, estriol and beta-HCG, with a 70% sensitivity and 5% false positive results. It is complemented in some regions of the U.S. as a quadruple addition of inhibin in the group, resulting in a 81% sensitivity and 5% false-positive rate of detecting down syndrome when taken at 15-18 weeks of gestational age and other prenatal diagnosis techniques, although it is still widely used in Canada and other countries. A positive test indicates an increased risk of chromosomal anomalies and neural tube defects, such patients are then directed to more sensitive and specific procedures to receive a definitive diagnosis, often prenatal diagnosis by amniocentesis, although stronger screening of variant cell-free fetal DNA screening also known as non-invasive prenatal screening is often offered. The triple test can be understood as an early predecessor to a long line of subsequent technological improvements. In some American States, such as Missouri, Medicaid reimburses only triple test and not other potentially more accurate screening tests, whereas California offers Quad tests to all pregnant women.