This is how they used it in an instruction for a remand:
the optometrist should be
asked to state the likelihood (i.e.,
probably (greater than 50 percent), at
least as likely as not (i.e., probability
of 50 percent), or less likely than not
(i.e., probability less than 50 percent)
that the service-connected diabetes
mellitus aggravated his glaucoma.