Dinse G E
Division of Biometry and Risk Assessment, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709.
Biometrics. 1988 Jun;44(2):405-15.
Tumor incidence is the primary measure of carcinogenesis. This article focuses on estimating time-dependent incidence rates in animal experiments with few sacrifices. When the context of observation is known for none or all of the animals dying with the tumor of interest, previous results are obtained under relaxed assumptions. The link with existing semiparametric and nonparametric procedures based on latent failure times is exploited by using these methods to compute maximum likelihood estimates of the incidence rates without introducing latent random variables. Nonparametric estimators that are appropriate when all contexts of observation are known are generalized to the case in which the contexts of observation are unknown for a subset of the tumor-bearing animals.
肿瘤发生率是致癌作用的主要衡量指标。本文着重于在牺牲动物数量较少的动物实验中估计随时间变化的发生率。当已知所有或没有动物死于感兴趣的肿瘤的观察背景时，可在较为宽松的假设下获得先前的结果。通过使用这些方法来计算发生率的最大似然估计值，而不引入潜在随机变量，从而利用了与基于潜在失效时间的现有半参数和非参数程序的联系。当所有观察背景都已知时适用的非参数估计器被推广到一部分患肿瘤动物的观察背景未知的情况。
