Due to dependent happenings, vaccines can have different effects in populations. In addition to direct protective effects in the vaccinated, vaccination in a population can have indirect effects in the unvaccinated individuals. Vaccination can also reduce person-to-person transmission to vaccinated individuals or from vaccinated individuals compared with unvaccinated individuals. Design of vaccine studies has a history extending back over a century. Emerging infectious diseases, such as the SARS-CoV-2 pandemic and the Ebola outbreak in West Africa, have stimulated new interest in vaccine studies. We focus on some recent developments, such as target trial emulation, test-negative design, and regression discontinuity design. Methods for evaluating durability of vaccine effects were developed in the context of both blinded and unblinded placebo crossover studies. The case-ascertained design is used to assess the transmission effects of vaccines. The novel ring vaccination trial design was first used in the Ebola outbreak in West Africa.

中文翻译：

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疫苗研究设计


由于依赖性事件，疫苗可能对人群产生不同的影响。除了对接种疫苗者的直接保护作用外，人群中的疫苗接种还会对未接种疫苗的个体产生间接影响。与未接种疫苗的个体相比，接种疫苗还可以减少向接种疫苗的个体或接种疫苗的个体的人际传播。疫苗研究的设计可以追溯到一个多世纪前。新出现的传染病，如 SARS-CoV-2 大流行和西非的埃博拉疫情，激发了人们对疫苗研究的新兴趣。我们重点介绍一些最近的发展，例如目标试验仿真、测试阴性设计和回归不连续性设计。评估疫苗效果持久性的方法是在盲法和非盲法安慰剂交叉研究的背景下开发的。病例确定的设计用于评估疫苗的传播效应。新型环围疫苗接种试验设计首次用于西非的埃博拉疫情。