Ghani A C, Donnelly C A, Cox D R, Griffin J T, Fraser C, Lam T H, Ho L M, Chan W S, Anderson R M, Hedley A J, Leung G M
Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom.
Am J Epidemiol. 2005 Sep 1;162(5):479-86. doi: 10.1093/aje/kwi230. Epub 2005 Aug 2.
During the course of an epidemic of a potentially fatal disease, it is important that the case fatality ratio be well estimated. The authors propose a novel method for doing so based on the Kaplan-Meier survival procedure, jointly considering two outcomes (death and recovery), and evaluate its performance by using data from the 2003 epidemic of severe acute respiratory syndrome in Hong Kong, People's Republic of China. They compare this estimate obtained at various points in the epidemic with the case fatality ratio eventually observed; with two commonly quoted, naïve estimates derived from cumulative incidence and mortality statistics at single time points; and with estimates in which a parametric mixture model is used. They demonstrate the importance of patient characteristics regarding outcome by analyzing subgroups defined by age at admission to the hospital.
在一种可能致命疾病的流行过程中，准确估计病死率非常重要。作者基于Kaplan-Meier生存程序提出了一种新的方法，同时考虑两种结局（死亡和康复），并利用中国香港2003年严重急性呼吸综合征疫情的数据评估了该方法的性能。他们将疫情不同阶段获得的这一估计值与最终观察到的病死率进行比较；与从单一时间点的累积发病率和死亡率统计得出的两个常用的简单估计值进行比较；还与使用参数混合模型得出的估计值进行比较。他们通过分析以入院时年龄定义的亚组，证明了患者特征对结局的重要性。
