Erebholo Francis, Bezandry Paul, Apprey Victor, Kwagyan John
Department of Mathematics, Hampton University, Hampton, Virginia 23668 USA.
Department of Mathematics, Howard University, Washington DC 20059 USA.
Appl Appl Math. 2016 Jun;11(1):83-96.
The problem of incomplete data is a common phenomenon in research that involves the longitudinal design approach. We investigate and develop a likelihood-based approach for incomplete longitudinal binary data using the disposition model when the missing value mechanism is non-ignorable. We combined Markov's transition and a logistic regression model to build the dropout process and model the response using conditional logistic regression model. By holding the missingness parameter that is weakly identified constant, we analyzed their effects through a sensitivity analysis as the estimation of parameters in MLE for non-ignorable missing data is not generally plausible. An application of our approach to Schizophrenia clinical trial is presented.
数据不完整问题是采用纵向设计方法的研究中的常见现象。当缺失值机制不可忽略时,我们使用处置模型研究并开发了一种基于似然的方法来处理不完整的纵向二元数据。我们将马尔可夫转移和逻辑回归模型相结合,以构建失访过程,并使用条件逻辑回归模型对响应进行建模。通过将弱识别的缺失参数保持为常数,我们通过敏感性分析来分析它们的影响,因为对于不可忽略的缺失数据,最大似然估计中的参数估计通常不太合理。本文展示了我们的方法在精神分裂症临床试验中的应用。