This says to me that testosterone is the culprit. I have seen some feminists claim that testosterone has nothing to do with criminality but there it is, right there in the stats -- what do men and TIFs have in common? Male levels of T, or at least much, much higher in TIFs than is normal for women, anyway.
And mental illness and testosterone do not play nicely together. When a woman has a schizophrenic break, you almost never hear about it. When a man has a schizophrenic break, he makes for a dangerous fellow Greyhound passenger.
I think it says a lot that every man I have spoken to about that study has never been surprised. Testosterone is a hell of a drug.
Long-Term Follow-Up of Transsexual Persons Undergoing Sex Reassignment Surgery: Cohort Study in Sweden