Developing control charts in monitoring service quality based on the number of customer complaints

Abstract

Service industry has become the primary driving force behind global economic growth. This means that ensuring service quality is an important issue. Unfortunately, the process of providing services includes a number of variables that are difficult to control. As a result, determining the means to ensure the quality of service is a popular theme of research. In the past, researchers have always used the proportion of customers with complaints to propose a service performance index for the evaluation of service quality; however, the index alone cannot guarantee timely monitoring. For this reason, based on the number of customer complaints, this study proposes a theory-based service quality control chart to assist company management in the timely monitoring of customer satisfaction to ensure that service quality is being maintained. According to the characteristics of the service industries, we divided them into those with large sample sizes and those with small sample sizes. For each type, we developed an appropriate service quality monitoring model and explained the operating procedures of the control charts to provide managers with a means to comprehensively monitor service quality.

Keywords:

• service quality
• customer complaints
• service performance index
• control chart
• monitoring

Acknowledgements

The author would like to thank the Editor, Professor Jens J. Dahlgaard, and anonymous referees for their helpful comments and careful reading, which significantly improved the presentation of this paper. This work is partially supported by Taiwan's National Science Council (Grant NSC 102-2221-E-167-028).