A STOPPING RULE FOR THE CONTINUAL REASSESSMENT METHOD

The continual reassessment method provides a new approach for estimati ng the maximum tolerated dose in a phase I clinical trial. In this pap er we investigate a potential stopping rule for this method. We indica te certain situations in which the finally chosen dose level can be pr edicted with certainty after having included a number of patients stri ctly less than the projected sample size. There is therefore a clear g ain when the only purpose of the trial is to identify a target dose fo r future experimentation. When prediction with certainty is not possib le, we can still estimate the probability that the current level will be the same as all subsequent recommended levels.