ON THE BECHHOFER-KULKARNI STOPPING RULE FOR SEQUENTIAL CLINICAL TRIALS.

A stopping rule recently introduced by Bechhofer and Kulkarni for sequential clinical trials is considered in the special case of relative evaluation of two procedures. Figures of merit are introduced for such trials and evaluated explicitly in terms of Legendre polynomial series by means of a sequence of generating functions modified to automatically include the required protocol. The expected trial duration is also evaluated asymptotically to reinforce the point that asymptotic methods can be effective in such situations for extremely short sequences.