Cumulative Sum Charts and Its Healthcare Applications; A Systematic Review

Abstract

Application of Statistical process control (SPC) is increasing being advocated in health science as a valuable quality improvement tool. The use of control charts in health science related applications differs somewhat from industrial. In SPC, cumulative sum (CUSUM) charts rather than Shewhart chart are used to detect smaller shifts in the process. In order to improve the detection capability relative to that of the Shewhart control charts, several control charts have been developed such as CUSUM charts, Exponentially weighted moving average(EWMA) charts and Sequential probability ratio test (SPRT) etc. Among them, the CUSUM charts are popular and effective. The CUSUM procedure has recently made its appearance in the field of medicine. The main purpose of this paper is to elucidate the common uses of CUSUM charts in healthcare and to describe different forms of CUSUM charts for monitoring performance over time when the outcome is related to health science.