University of Washington Lip-Philtrum guide

(A) Lip-Philtrum Guides 1 and 2 are used to rank upper lip thinness and philtrum smoothness. The philtrum is the vertical groove between the nose and upper lip. The guides reflect the full range of lip and philtrum shapes with Rank 3 representing the population mean. Ranks 4 and 5 reflect the thin lip and smooth philtrum that characterize the fetal alcohol syndrome (FAS) facial phenotype. Guide 1 is used for White Americans and all other races with lips like White Americans. Guide 2 is used for African Americans and all other races with lips as full as African Americans.
(B) The lips and philtrum should be assessed with the lips gently closed and no smile. As depicted above, smiling causes the lips and philtrum to appear thinner and smoother, respectively, than they truly are.