Tane Ikai

Tane Ikai - 116 years, 175 days, Japan
Tane Ikai died in Japan in 1995 when she is claimed to have been over 116 years old. A one page report was published in 2010 by a US/European team [48], but it only gives biographical details with no reference to sources. We are not told if the details came from official records, family testimony, another validation report, or just press reports.

Unusually an autopsy was performed by German doctor Doerr from the University of Heidelberg. Some details were published in a book by Hans Franke revealing that she died of kidney failure. However, this does nothing to help validate her longevity. The GRG lists showed her to have also been validated by the Japanese group. References point back to a 1997 Japanese book [78] but this is inaccessible and may just focus on the autopsy.

She would have been born in January 1879 when the Koseki system of birth registration had been is use for just seven years. Koseki records did not contain full birth dates until 1915 and may be unreliable even after that time. We do not know which Koseki was obtained, if any, to verify her age. It is possible that she was only verified using records from the Resident Registry System as described in [46].

To be reliable her validation would need some official Koseki record along with other early documents such as school records, photographs and family testimony. Since she died 26 years ago we doubt that such an in-depth investigation was carried out. There has been plenty of time to publish any details of sources that were available, but nothing has come forward. Since family cooperation is now required to obtain any Koseki or residential documents it is unlikely that further work will be done on her validation.

Under these circumstances there is a high risk that the longevity claim of Tane Ikai could have come about by age exaggeration as has been shown to have happened for other previously validated Japanese claims. She is also reported to have had a daughter who died aged 47, so an identity switch also needs to be ruled out with some additional evidence.

In the absence of a conventional validation report it can be assumed that she was at least auto-validated according to the procedures described in [46]. We have seen from the validation reports of Misao Okawa and Chiyo Miyako that validators have been content to rely on Koseki that were created long after birth when new families are formed after marriage. There is no guarantee that these documents have been copied faithfully from originals, or that they were accurate in the first place, or that they did not suffer from war-time damage. It is possible that the longevity claim is correct but without the same standard of evidence that is required in other countries we cannot accept the longevity as correctly verified.