Content area
Testo completo
1. Introduction
Six Sigma has been successfully implemented worldwide for > 25 years, producing significant savings to the bottom-line of many large and small organizations (Treichler, 2005). It is a disciplined, systematic and data-driven approach to process improvement that targets the near-elimination of defects from every product, process and transaction (Firka, 2010; Montgomery, 2010). This approach has been widely used to improve performances and reduce costs for several industrial fields (Kaushik et al., 2012). The aim of such a methodology is not only to improve the process but also to ensure that gains made are sustained (Snee, 2004).
The application of Six Sigma is growing and moving from the manufacturing field to encompass all business operations, such as services, transactions, administration, Research & Development (R&D), sales and marketing and especially to those areas that directly affect the customer (Hahn et al., 2000). It starts with a business strategy and ends with top-down implementation, with a significant impact on profit if successfully deployed (Breyfogle, 2003). As a project-driven management approach, the range of Six Sigma applications is also growing from reduction of defects in an organization's processes, products and services to become a business strategy that focuses on improving understanding of customer requirements, business productivity and financial performance (Kwak and Anbari, 2006; Heavey and Murphy, 2012). Even though implementation of Six Sigma started in the manufacturing industry, nowadays it is being implemented in a variety of fields including low-volume complex environment to small- and medium-sized enterprises for addressing different types of business- and process-related problems (Tjahjono et al., 2010; Julien and Holmshaw, 2012; Deshmukh and Chavan, 2012). There has been a lot of further research carried out in various aspects of Six Sigma implementation, including comparison of this method with various other initiatives and integrating the Six Sigma methodology with other initiatives (Chiarini, 2011; Jeyaraman and Teo, 2010; Lagrosen et al., 2011; Leon et al., 2012).
Define-Measure-Analyze-Improve-Control (DMAIC) framework of Six Sigma methodology has been well established as a benchmarking tool for process improvement and customer satisfaction (Chen et al., 2005; Snee, 2010). DMAIC process improvement cycle begins with the definition of a problem, followed by the measurement of baseline performance. Suitable target variables are then identified and mapped against...