Hakko H, Räsänen P, Tiihonen J
Department of Psychiatry, University of Oulu, Finland.
Acta Psychiatr Scand. 1998 Aug;98(2):92-7. doi: 10.1111/j.1600-0447.1998.tb10048.x.
The aim of this study was to investigate the age-, gender- and suicide method-related seasonality of suicide occurrence by using the largest database examined so far (n=21,279). The Chi-square test for multinomials was used as the overall measure of deviation. The monthly observed and expected numbers of suicides were calculated and classified by year, month, gender, age groups and suicide methods. To identify the statistically significant peak and trough months, the ratio of observed numbers of suicides to expected numbers with 95% confidence intervals was calculated. For males, there was a suicide peak from April to July, while for females the distribution was bimodal (with peaks in May and October). In elderly people there was a significant excess in the number of suicides in autumn, and the troughs were deeper in winter. For violent suicides there was a unimodal spring peak, but for non-violent suicides the distribution was bimodal. The results indicate that suicides among elderly subjects, as well as non-violent suicides, occur significantly more often during autumn than would be expected.
本研究旨在通过使用迄今为止所研究的最大数据库（n = 21279）来调查自杀发生的与年龄、性别和自杀方式相关的季节性。多项卡方检验被用作偏差的总体度量。计算每月自杀的观察数和预期数，并按年份、月份、性别、年龄组和自杀方式进行分类。为了确定具有统计学意义的高峰和低谷月份，计算了观察到的自杀数与预期数的比率以及95%置信区间。对于男性，4月至7月存在自杀高峰，而对于女性，分布是双峰的（5月和10月有高峰）。在老年人中，秋季自杀人数显著过多，冬季低谷更深。对于暴力自杀，有一个单峰的春季高峰，但对于非暴力自杀，分布是双峰的。结果表明，老年受试者的自杀以及非暴力自杀在秋季发生的频率明显高于预期。
