Triple test Triple test The triple test, also called triple screen, the Kettering test or the Bart's 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 (and neural tube defects). 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 rate. It is complemented in some regions of the United States, as the "Quad screen" (adding inhibin A to
Owned-and-operated television stations in the United States its partnership, in November 1993 (fourteen months before the network debuted), Tribune agreed to a deal to affiliate most of its independent stations with The WB. Despite Tribune's minority stake, the company's stations were not considered to be WB owned-and-operated-stations due to Time Warner's controlling interest in the network. This resulted in The WB having the unusual distinction of being the only broadcast network that did not have O&Os in New York City, Los Angeles and Chicago throughout its existence (the three Tribune-owned WB affiliates in those cities – WPIX, KTLA and WGN-TV, respectively – were "affiliates" of the network