Abstract
Many procedures have been introduced to improve the efficacy and performance of the exponentially weighted moving average (EWMA) control chart. The objective of these research studies is to introduce an efficient and precise monitoring method to detect smaller shifts in the process mean. Azam et al. [1] presented a new control chart called hybrid exponentially weighted moving average (HEWMA); where they have developed a new model and derived new control schemes. However, minor mistakes were observed in the article. This note will modify Azam et al.'s article in order to get the maximum benefit out of their proposed new model.