<big-snip> > > Male > > Female > > Hermaphrodite > > This read, "Intersexed" > > > Trans (MTF) > > Trans (FTM) > > Neuter > > > > and... I can't think of a seventh possibility. > > "Decline to state" ISO 5218 takes 22 pages to give us four oddly placed values for male, female, and two versions of null, "unknown" and "not aplicable." Interestingly, it doesn't include "declined to state." The values are as previously stated: 0 = unknown 1 = male 2 = female 9 = not aplicable As pointed out above, there really are more legitimate values. To track all of them and still be aproximagely ISO compatible, I propose the following. Based on the observation that ISO 5318 mathematically specifies male as odd and female as even, the y-chromosome containing sexes (which include hermaphrodites), shall be odd. This leaves unknown, as even, and perhaps neuter can be not aplicable, since we don't know. ... This does leave "declined to state" as a valid form of "null."
