Heterosexual erotic videos. The neural correlates of subjective pleasantness.
Sexual arousal patterns of bisexual men revisited.
Michael Bailey in:
Hypothalamic response to the chemo-signal androstadienone in gender dysphoric children and adolescents.
The scale ranged from 0 to 6, with 0 corresponding to an exclusively heterosexual orientation and 6 corresponding to an exclusively homosexual orientation.