Ye Wen, Isaman Deanna Jm, Barhak Jacob
Department of Biostatistics, School of Public Health, University of Michigan, 1415 Washington Heights, Ann Arbor, Michigan 48109-2029.
Inf Fusion. 2012 Apr 1;13(2):137-145. doi: 10.1016/j.inffus.2010.08.003. Epub 2010 Sep 6.
With the increasing burden of chronic diseases on the health care system, Markov-type models are becoming popular to predict the long-term outcomes of early intervention and to guide disease management. However, statisticians have not been actively involved in the development of these models. Typically, the models are developed by using secondary data analysis to find a single "best" study to estimate each transition in the model. However, due to the nature of secondary data analysis, there frequently are discrepancies between the theoretical model and the design of the studies being used. This paper illustrates a likelihood approach to correctly model the design of clinical studies under the conditions where 1) the theoretical model may include an instantaneous state of distinct interest to the researchers, and 2) the study design may be such that study data can not be used to estimate a single parameter in the theoretical model of interest. For example, a study may ignore intermediary stages of disease. Using our approach, not only can we accommodate the two conditions above, but more than one study may be used to estimate model parameters. In the spirit of "If life gives you lemon, make lemonade", we call this method "Lemonade Method". Simulation studies are carried out to evaluate the finite sample property of this method. In addition, the method is demonstrated through application to a model of heart disease in diabetes.
随着慢性病给医疗保健系统带来的负担日益加重，马尔可夫型模型在预测早期干预的长期结果以及指导疾病管理方面越来越受欢迎。然而，统计学家尚未积极参与这些模型的开发。通常，这些模型是通过二次数据分析来开发的，以找到一项单一的“最佳”研究来估计模型中的每个转变。然而，由于二次数据分析的性质，理论模型与所使用研究的设计之间经常存在差异。本文阐述了一种似然方法，用于在以下条件下正确地对临床研究设计进行建模：1）理论模型可能包括研究人员特别感兴趣的瞬时状态；2）研究设计可能使得研究数据无法用于估计感兴趣的理论模型中的单个参数。例如，一项研究可能会忽略疾病的中间阶段。使用我们的方法，我们不仅可以适应上述两个条件，而且可以使用不止一项研究来估计模型参数。本着“如果生活给你柠檬，就把它做成柠檬汁”的精神，我们将这种方法称为“柠檬汁法”。进行了模拟研究以评估该方法的有限样本性质。此外，通过将该方法应用于糖尿病心脏病模型进行了演示。
