Protective isolation and antimicrobial decontamination in patients with high susceptibility to infection. A prospective cooperative study of gnotobiotic care in acute leukemia patients. II. Organizational and statistical concept.

The organizational and statistical concept of the cooperative randomized controlled clinical trial on gnotobiotic care and its effect in acute leukamia patients is described. The purpose is the clarification of the concept of the study and the comparison with other studies on the same subject. It is concluded that the value of the results and of the decisions based on them depend mainly on the statistical design, the protocol, and the performance of a study. The performance of a controlled study depends on its organizational details, its monitoring, documentation, and appropriate biometric evaluation. In this particular study it proved fruitful that a statistician was engaded in the evaluation and also in developing the protocol and in carrying out the study.