Figure 5.

The Hoyme FAS face is substantially relaxed relative to the 4-Digit Code FAS face.

A) The 4-Digit Code uses the Facial ABC-Score to document all combinations of expression of the 3 FAS facial features. These ABC-Scores are clustered to define the 4-Digit Code Face Ranks 1–4. The 4-Digit Code FAS facial phenotype is defined by a single ABC-Score (Facial ABC-Score CCC, Face Rank 4). B) In contrast, the relaxation of the Hoyme et al. FAS facial criteria (e.g., only 2 of 3 features required, PFL relaxed to 10^th percentile, and Rank 4 lip relaxed to 4-Digit Rank 2 lip) results in most every 4-Digit Code Facial ABC-Score meeting the relaxed criteria, including ABC-Scores that define Face Ranks 1 and 2. Clinically, the 4-Digit Code classifies Rank 1 and 2 facial phenotypes as being within the normal range. (FAS facial phenotype from Hoyme et al, 2016 used with permission from the American Academy of Pediatrics).