February, 2003
© 2000, 2001 Scott S. Emerson, M.D., Ph.D.
Statistical issues
due to rare events
Invariably,
there is very little statistical precision to establish increased
rates of Serious Adverse Experiences (SAEs) or increased rates of
individual toxicities
·As a general
rule, the DSMB therefore must act based on their prior
knowledge and principles of conservatism
-E.g.,
decisions to modify entry criteria by age due to statistically
nonsignificant trends in the data