Quality assurance programs in clinical trials.

Quality assurance programs attempt to assess the uniformity of compliance with a stated study program so that the results from one institution will indeed be comparable to those of all of the other institutions in the group. In the best situation, it should be easy to compare results from one group to those of any other group and any other studies of the same disease, because the basis of selection of the patient population, the treatment of patients, and the endpoints have been uniformly defined throughout. The evaluation of the end results includes a quantitative assessment of the appropriateness of these parameters. Quality assurance programs document the validity of interinstitutional, intergroup, and international studies. They are time-consuming and costly. They can be ulcerogenic. But, in the end, they are the firm basis upon which the statistical analysis can proceed.