Oguma S, Yoshida Y, Uchino H, Maekawa T
Cancer Res. 1987 Apr 15;47(8):2196-8.
The cumulative leukemia-free survival rate of refractory anemia with excess of blasts was fitted to three parametric failure time models, i.e., the usual exponential and Weibull, and exponential mixture models. Among the three, the best fit model was the exponential mixture model, which was 119 times more likely to assume that samples came from the exponential mixture distribution than to assume that those were from the usual Weibull distribution. This strongly suggests that refractory anemia with excess of blasts consists of subgroups with very high and very low probability to develop acute nonlymphoblastic leukemia. The estimated proportion of the very low probability group was about 30%. Analysis by the exponential mixture model with covariates revealed that the probability of a patient to develop acute nonlymphoblastic leukemia could be estimated by three covariates, i.e., bone marrow blast percentage; abnormal granules of granulocytes; and mononuclear large megakaryocytes. The estimated probabilities ranged from 17 to 99%, according to the model.
伴有原始细胞增多的难治性贫血的累积无白血病生存率采用三种参数失效时间模型进行拟合，即通常的指数模型和威布尔模型以及指数混合模型。在这三种模型中，最佳拟合模型是指数混合模型，该模型认为样本来自指数混合分布的可能性比来自通常威布尔分布的可能性高119倍。这有力地表明，伴有原始细胞增多的难治性贫血由发展为急性非淋巴细胞白血病概率非常高和非常低的亚组组成。极低概率组的估计比例约为30%。带有协变量的指数混合模型分析显示，患者发展为急性非淋巴细胞白血病的概率可通过三个协变量进行估计，即骨髓原始细胞百分比、粒细胞异常颗粒和单核大巨核细胞。根据该模型，估计概率范围为17%至99%。
