Assessing the evidence of Six Sigma and Lean in the health care industry

Qual Manag Health Care. 2010 Jul-Sep;19(3):211-25. doi: 10.1097/QMH.0b013e3181eb140e.


Background: Popular quality improvement tools such as Six Sigma and Lean Systems (SS/L) claim to provide health care managers the opportunity to improve health care quality on the basis of sound methodology and data. However, it is unclear whether these 2 quality improvement tools actually improve health care quality.

Methods: The authors conducted a comprehensive literature review to assess the empirical evidence relating SS/L to improved clinical outcomes, processes of care, and financial performance of health care organizations.

Results: The authors identified 177 articles on SS/L published in the last 10 years. However, only 34 of them reported any outcomes of the SS/L projects studied, and less than one-third of these articles included statistical analyses to test for significant changes in outcomes.

Conclusions: This review demonstrates that there are significant gaps in the SS/L health care quality improvement literature and very weak evidence that SS/L improve health care quality.

Publication types

  • Review

MeSH terms

  • Cost-Benefit Analysis
  • Efficiency, Organizational*
  • Evidence-Based Practice
  • Health Care Sector
  • Humans
  • Outcome and Process Assessment, Health Care / methods*
  • Quality of Health Care*
  • Total Quality Management / methods*