Fukunishi I, Hayabara T, Hosokawa K
Psychiatric Research Institute of Tokyo, Japan.
Int J Soc Psychiatry. 1991 Spring;37(1):51-6. doi: 10.1177/002076409103700107.
Epidemiological surveys of senile dementia at home were carried out on 3,754 subjects for two consecutive years, 1987 and 1988. The prevalence and incidence rates were 4.1% and 1.01%, respectively. Concerning the incidence rate, the sample populations of previous reports were small in number--less than 1,000. If we suppose that the incidence were to be approximately 1%, then it follows that dementia would be noted yearly in no more than one out of 100 senile subjects. A difference in subject number leads to a great difference in the incidence. Therefore, it is necessary that the number of subjects should be more than 1,000 for a comprehensive epidemiological survey of incidence rate of senile dementia. Accordingly, the present study is a better representation of the true picture as it was obtained by a more accurate method accompanied by less errors.
1987年和1988年连续两年对3754名受试者进行了国内老年痴呆症的流行病学调查。患病率和发病率分别为4.1%和1.01%。关于发病率，以往报告的样本数量较少，不足1000人。如果我们假设发病率约为1%，那么由此可知，每100名老年受试者中每年出现痴呆症的人数不超过1人。样本数量的差异会导致发病率出现很大差异。因此，对老年痴呆症发病率进行全面的流行病学调查时，样本数量应超过1000人。相应地，本研究通过更准确的方法且误差较小，能更好地反映真实情况。
