A strategy for cancer prevention and control research.

Cancer is an important cause of morbidity and mortality in industrial countries. Recently changes in life-style and the environment in developing countries have coincided with increases in the incidence of certain cancers which might be related to these factors. A strategy for the prevention of all such cancers is presented, which involves research in a sequence of five phases to identify suitable interventions and to confirm their effectiveness in population studies, prior to their application on a nationwide scale.