1Age validation of Han Chinese centenarians By

Age validation of centenarians and gathering data about the demographic patterns and health status of centenarians have become a research area of importance because populations in most countries are aging. China’s population, in particular, is aging at an extraordinarily rapid rate (Banister, 1990; Ogawa, 1988; Zeng and Vaupel, 1989). Centenarians used to be exceedingly rare. They are still rare today, but the number of centenarians is now doubling approximately every decade (Kannisto 1994, Vaupel and Jeune 1995). The average annual growth rates in the 1970s and 1980s in the number attaining age 100 were, for example, 10.2%, 9.2%, and 9.1 % in Japan, Switzerland, and West Germany respectively (Vaupel and Jeune, 1995, p. 112). If current rates of mortality improvement persist, then it will be as likely for a child born today to reach age 100 as it was for a child born eight decades ago to reach age 80 (Vaupel and Gowan, 1986). Despite high mortality in the past, China has a large number of elderly people, because the Chinese population is so huge, currently totallin