Evaluating the alangesic effect of a daily dose of methadone.

Subjects given both placebo and methadone, in random order, in a 
double blind fashion.

Outcome:  measure of maximum pain (0=none, 100=severe) on placebo 
(Plac) or methadone (Meth).

Is there sufficient evidence to conclude at the 0.05 level of 
signifcance that methodone lowers the intensity of pain?