A theoretical and statistical approach of Six Sigma differentiation from other quality systems

Purpose: The purpose of this paper is to investigate in which management aspects could Six Sigma (SS) methodology help the organization that implements it. Another subject to be examined is the integration of SS and other quality management systems (QMSs) in practice and in a theoretical way. Design/methodology/approach: A questionnaire was addressed to 146 Greek companies of all business sectors, with at least one QMS; here was ISO 9001:2008. It included questions concerning the importance of the critical success factors (CSFs) of QMSs and performance measures after the implementation of ISO 9001. Correspondence analysis was used for the analysis of the data. A theoretical investigation in literature was also accomplished to express the characteristic aspects of SS. Findings: Companies implementing SS seemed to outperform the companies without it, in the importance given in most CSFs and equally in the performance measures. People-oriented factors distinguished as more important, and this is consistent with the literature concerning SS. Practical implications: This paper provides information for practitioners and researchers about SS methodology and presents some of its advantages, deriving from its integration with ISO 9001 QMS. Originality/value: It makes available a perspective of SS deployment in Greek organizations. It also clarifies points that demonstrate the differentiation of SS from other quality approaches and the case of integration with ISO 9001. It also presents the demographic profile of the companies that implement SS.