Describes problems in implementing placebo controls in psychotherapy including the difficulty of ensuring that therapists and their patients will view both the experimental and placebo treatments as comparably credible. Considers six research issues stemming from the definitional requirement that the placebo control for the critical and specific…

An examination of the scientific basis of both control group designs and comparative designs in outcome research reveals that comparative designs generally have fewer threats to validity and provide a more efficient means of control for nonspecific treatment factors suggesting that comparative studies warrant a larger role in the study of…

Treatment outcomes are distinguished as ultimate, instrumental, and intermediate in terms of the role that they play in the treatment process. These distinctions between outcomes are proposed to facilitate a more discriminating view of the treatment process and thus contribute to the design of evaluative studies. (Author)