The role of sampling in clinical trial design.

A treatment's recovery rate depends upon the percentage of clients who received the treatment and recovered. This rate is not logically interpretable as the personal probability of recovery of any individual client assigned to this treatment unless the rate is 0% or 100%. So clinical trials need to be designed to help us learn how to distinguish before treatment the sorts of clients who recover in response to each available form of treatment from those who do not. This requires our developing sufficiently comprehensive sampling of clients and client covariates as part of the design of clinical trials, which would be more likely and efficiently achieved were there centralized programmatic planning and coordination of the development of these aspects of clinical trial design.