Accelerated failure time model based risk adjusted MA-EWMA control chart.

In health care centers, monitoring the medical outcomes is desirable to quickly detect performance changes. In recent years, monitoring the surgical process has gained eminence by accounting for patients' health conditions before cardiac surgery where the data is heterogeneous with respect to patients' health conditions. In the current study, we focus on risk-adjusted moving average-exponentially weighted moving average (RAMA-EWMA) control chart to identify the survival time after cardiac surgery. For this purpose, we used two years data set of the cardiac surgery. The performance of the control chart is evaluated by the average run length. Based on the extensive simulation, the average run length properties are computed. It is revealed that the proposed control chart has better shift diagnostic ability than the control chart considers in this study. [ABSTRACT FROM AUTHOR]