Species of evidence of exceptional longevity
In: Jeune, B., Vaupel, J. W.
(Eds.): Validation of exceptional longevity
Odense Monographs on Population Aging 6
Odense, Odense University Press (1999)
ISBN 87-7838-466-4 / ISSN 0909-119X
"Most reported instances of exceptional longevity are incorrect. This was the rule everywhere until the end of the 19th century and is still the case in the vast majority of countries. Previous monographs in this series have documented the proliferation of centenarians since 1950 . In Japan and the countries of Western Europe, the only countries with time series of valid data at advanced ages… Although today age reports in the Nordic countries are exceptionally acurate…. Until then in Sweden and Denmark - and still today in most countries - age statistics were based on self-reported ages in censuses or unverified ages reported on death certificates. It is only when reliable birth registrations are available for a century ore more and when reports of ages above 100 are systematically checked against these data that the quality of natinal statistics on exceptional longevity improves." (EXCERPT)