Assessing the evidence of Six Sigma and Lean in the health care industry.
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.
DelliFraine
Jami L
JL
Division of Management, Policy, and Community Health and Fleming Center for Healthcare Management, University of Texas School of Public Health, Houston, TX 77030, USA.
Langabeer
James R
JR
Nembhard
Ingrid M
IM
D003362:Cost-Benefit Analysis; D017598:Efficiency, Organizational; D055317:Evidence-Based Practice; D019981:Health Care Sector; D006801:Humans; D010043:Outcome and Process Assessment, Health Care / Q000379:methods*; D011787:Quality of Health Care; D017749:Total Quality Management / Q000379:methods*