-
Inverted Pyramid of Care.
Sonek JD, Kagan KO, Nicolaides KH.
Clin Lab Med 2016;36:305-17. pdf -
First trimester maternal serum AFP and total hCG in aneuploidies other than trisomy 21.
Spencer K, Heath V, Flack N, Ong C, Nicolaides KH.
Prenat Diagn 2000;20:635-9.