The existence of immune or cured individuals in a population and whether there is sufficient followup in a sample of censored observations on their lifetimes to be confident of their presence are questions of major importance in medical survival analysis. So far only a few candidates have been put forward as possible test statistics for the existence of sufficient followup in a sample. Here we investigate one such statistic and give a detailed analysis, obtaining an exact finite sample as well as asymptotic distributions for it, and use these to calculate the power of the test as a function of the followup in the sample.

翻译：免疫性或治愈性个人在人口中的存在,以及在对其一生的检查性观察抽样中是否有足够的后续行动,以确信其存在是医学生存分析中至关重要的问题,迄今为止,只有少数候选人被作为可能的测试统计数据,以证明在抽样中是否有足够的后续数据。 我们在这里调查一个此类统计数据,并对此进行详细分析,获得精确的有限样本以及对其的药用分布,并利用这些数据计算测试的功率,作为样本中后续数据的函数。