INTERNATIONAL JOURNAL OF INFORMATION TECHNOLOGY & DECISION MAKING

Pattern Recognition of Longitudinal Trial Data with Nonignorable Missingness: An Empirical Case Study
Fang H, Espy KA, Rizzo ML, Stopp C, Wiebe SA and Stroup WW
Methods for identifying meaningful growth patterns of longitudinal trial data with both nonignorable intermittent and drop-out missingness are rare. In this study, a combined approach with statistical and data mining techniques is utilized to address the nonignorable missing data issue in growth pattern recognition. First, a parallel mixture model is proposed to model the nonignorable missing information from a real-world patient-oriented study and concurrently to estimate the growth trajectories of participants. Then, based on individual growth parameter estimates and their auxiliary feature attributes, a fuzzy clustering method is incorporated to identify the growth patterns. This case study demonstrates that the combined multi-step approach can achieve both statistical gener ality and computational efficiency for growth pattern recognition in longitudinal studies with nonignorable missing data.