CD4-based multi-state back-calculation methods are key for monitoring the HIV epidemic, providing estimates of HIV incidence and diagnosis rates by disentangling their inter-related contribution to the observed surveillance data. This paper, extends existing approaches to age-specific settings, permitting the joint estimation of age- and time-specific incidence and diagnosis rates and the derivation of other epidemiological quantities of interest. This allows the identification of specific age-groups at higher risk of infection, which is crucial in directing public health interventions. We investigate, through simulation studies, the suitability of various bivariate splines for the non-parametric modelling of the latent age- and time-specific incidence and illustrate our method on routinely collected data from the HIV epidemic among gay and bisexual men in England and Wales.

中文翻译：

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扩展贝叶斯反算来估计年龄和时间特定的艾滋病毒发病率。

基于 CD4 的多状态反算方法是监测 HIV 流行的关键，通过解开它们对观察到的监测数据的相互关联的贡献来提供 HIV 发病率和诊断率的估计。本文将现有方法扩展到特定年龄环境，允许联合估计特定年龄和特定时间的发病率和诊断率，并推导其他感兴趣的流行病学数量。这可以识别感染风险较高的特定年龄组，这对于指导公共卫生干预措施至关重要。我们通过模拟研究调查了各种双变量样条对潜在年龄和时间特定发病率的非参数建模的适用性，并说明了我们对英格兰和威尔士同性恋和双性恋男性中艾滋病毒流行情况常规收集的数据的方法。