[Centenarian--a contribution to longevity research].

During the last two decades an increase of research on centenarians can be observed. There are two aspects, which were analyzed mainly: 1. the problems of antecedents of extreme longevity and 2. the state of psycho-physical well-being of these very old persons. We analyzed some newer international studies on centenarians and discussed especially the findings of the "Würzburger Centenarian-Study" of Hans Franke and his staff. Aside from this a report is given on a biographical study on 40 centenarians from the Bonn-Cologne area under the special aspect of coping-styles. From these and other studies a high degree of interindividual variability can be concluded even in this very old-age group. There apparently is no age-limit for the maintenance of interindividual differences in aging as predicted by some authors. And there is no general age-limit for the maintenance of independence and social competence.