Durham L K, Longini I M, Halloran M E, Clemens J D, Nizam A, Rao M
Department of Biostatistics, The Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA.
Am J Epidemiol. 1998 May 15;147(10):948-59. doi: 10.1093/oxfordjournals.aje.a009385.
The authors present a nonparametric method for estimating vaccine efficacy as a smooth function of time from vaccine trials. Use of the method requires a minimum of assumptions. Estimation is based on the smoothed case hazard rate ratio comparing the vaccinated with the unvaccinated. The estimation procedure allows investigators to assess time-varying changes in vaccine-induced protection, such as those produced by waning and boosting. The authors use the method to reanalyze data from a vaccine trial of two cholera vaccines in rural Bangladesh. This analysis reveals the differential protection and waning effects for the vaccines as a function of biotype and age.
作者提出了一种非参数方法，用于根据疫苗试验将疫苗效力估计为时间的平滑函数。该方法的使用需要最少的假设。估计基于比较接种疫苗者与未接种疫苗者的平滑病例风险率比。该估计程序使研究人员能够评估疫苗诱导的保护作用随时间的变化，例如由抗体衰减和加强产生的变化。作者使用该方法重新分析了孟加拉国农村地区两种霍乱疫苗的疫苗试验数据。该分析揭示了疫苗作为生物型和年龄函数的差异保护和衰减效应。
