Cluster randomized trials (CRTs) are increasingly used to study the efficacy of interventions targeted at the population level. Formulae exist to calculate sample sizes for CRTs, but they assume that the domain of the outcomes being considered covers the full range of values of the considered distribution. This assumption is frequently incorrect in epidemiological trials in which counts of infection episodes are right-truncated due to practical constraints on the number of times a person can be tested.

中文翻译：

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具有右截断的Poisson分布结果的集群随机试验（CRT）的功效计算：来自疟疾媒介控制试验的一个启发性例子。

整群随机试验（CRT）越来越多地用于研究针对人群水平的干预措施的有效性。存在用于计算CRT的样本量的公式，但是它们假定要考虑的结果域涵盖了所考虑的分布的所有值范围。这种假设在流行病学试验中常常是不正确的，在流行病学试验中，由于实际检查人的次数受到限制，因此感染发作的计数被截断了。