Six Sigma: a literature review analysis

Six Sigma (SS) methodology is nowadays one of the most used approaches in the Quality Management field since its benefits coming from the improvement of the process outputs quality by identifying and removing the causes of defects and variability in manufacturing and business processes. Thus, literature on the SS topic is exponentially increased during last decades; the vast number of works on the SS field represents a good opportunity for a structured literature review of the articles, in order to understand the evolutions of the concept, the fields of its application and possible evolution for further studies. The literature review has been carried out by using a chronological review of the main SS approaches developed both for large and small companies, in order to highlight particular aspects of the SS literature and some applications of the SS methodology. The evaluation of the papers found in literature is carried out through a Strengths-Weaknesses criterion. Moreover, for those treating the application of the SS methodology into both big companies both Small & Medium Enterprises (SMEs), an assessment has been carried out based on the accordance with some milestones identified as necessary for every SS system. Finally the paper argues the possible further developments of the research field.