A general adaptive allocation design for continuous responses in the presence of covariates

Several adaptive allocation designs are available in the clinical trial literature for allocating the entering patients among two competing treatments, having binary responses and skewing the allocation in favor of the better treatment. No adaptive design is available for continuous responses in the presence of prognostic factors, which is not model based. In the present paper, a general allocation design is introduced which assumes no specific regression model or distribution of responses. Some performance characteristics of the design are studied. Some related inference, following the allocation, is also studied. The proposed procedure is compared with some possible competitors. A real data set is used to illustrate the applicability of the proposed design.