Gibbons R D, Clark D C, Fawcett J
Center for Suicide Research and Prevention, Department of Psychiatry, Rush Medical College, Chicago, IL.
Am J Epidemiol. 1990 Jul;132(1 Suppl):S183-91. doi: 10.1093/oxfordjournals.aje.a115781.
The absence of any standard definition of suicide cluster events hinders understanding of the prevalence of the problem, hinders the development of appropriate public health responses to observed clusters, and ultimately hinders investigation of the mechanisms underlying contagious communication of suicidal behavior. The authors introduce a Poisson mixture model for assessing potential clusters of adolescent suicide, apply that model to the monthly incidence rates of adolescent suicide for one populous US county over the last 11 years, and generate 99% tolerance limits with 95% confidence for the number of suicides which may occur by chance within specific intervals of time in that county. The suicide incidence data showed a remarkable fit to a single Poisson distribution, suggesting it is not unreasonable to consider the cases as randomly-distributed and independent events. The authors conclude that there is no evidence that adolescent suicides occurred in clusters in the place and in the time frame under study, and recommend the Poisson mixture model for ascertaining clusters as well as implementing cluster surveillance.
缺乏自杀聚集事件的任何标准定义阻碍了对该问题患病率的理解，阻碍了针对观察到的聚集情况制定适当的公共卫生应对措施，最终阻碍了对自杀行为传染性传播潜在机制的调查。作者引入了一种泊松混合模型来评估青少年自杀的潜在聚集情况，将该模型应用于美国一个人口众多的县过去11年青少年自杀的月发病率，并为该县特定时间间隔内可能偶然发生的自杀人数生成了95%置信度的99%容忍限。自杀发病率数据与单一泊松分布拟合得非常好，这表明将这些案例视为随机分布且相互独立的事件并非不合理。作者得出结论，在所研究的地点和时间范围内，没有证据表明青少年自杀是以聚集形式发生的，并建议使用泊松混合模型来确定聚集情况以及实施聚集监测。
