Application of Six Sigma Methodology in the Service Industry to Improve Process Efficiency and Customer Satisfaction: Systematic Review

The service industry is currently facing significant challenges related to process inefficiencies and low customer satisfaction. While the Six Sigma methodology has been extensively applied in manufacturing, its potential in the service sector remains underexplored. Therefore, this systematic literature review aims to fill this research gap by evaluating the application of Six Sigma in the service industry to improve process efficiency and customer satisfaction. The main objectives of this review include the identification of Six Sigma applications in the service sector, barriers to implement Six Sigma and frequent issues in the service sector, Six Sigma related Key Performance Indicators (KPIs) to measure process efficiency and customer satisfaction and to make a comparative analysis of Six Sigma with alternative methodologies to improve process efficiency and customer satisfaction. For that, this review uses the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method and thematic analysis to identify key themes and categorize barriers. The study spans the past decade, offering a comprehensive overview of Six Sigma’s applicability across various service sectors and regions. Results show that Six Sigma significantly improves operational efficiency and customer satisfaction across service sectors like Financial, Telecommunications, Healthcare, and Education. Overall, this review highlights the need for further research on Six Sigma’s implementation in the service sector. Thus, this research is vital for developing strategies to enhance process efficiency and customer satisfaction in the service industry through Six Sigma.