• Westat, Inc., Rockville, Maryland, USA.

The Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial is a large and complex multi-institutional, multifaceted organization with a 20-year horizon. The implementation of the trial began with the creation of an organizational structure that supports strong leadership, cooperation, and effective communication among the trial collaborators including an operational framework for the development, review, and pretest of instruments, data collection, and management procedures; the setting of high-quality standards for training of trial staff; and the development of a comprehensive assessment plan for evaluation of all trial activities. This paper describes the process and methods used in the coordination and management of the PLCO trial. These include the role of the steering committee and its subcommittees and working groups, the establishment of regular and ad hoc communications among collaborators, the training of screening center coordinators and examiners, the PLCO manual of operations and procedures, and the development and implementation of a comprehensive quality assurance plan.