Six Sigma is the commonly used term for a business quality control approach. Motorola developed it in 1986 and it has since been used successfully in many manufacturing processes. The term refers to the mathematical concept of “standard deviation.” Something that is six standard deviations outside the mean, or norm, is so rare as to have less than a one in a million chance of occurring. In terms of manufacturing, a six sigma goal is to have fewer than one in a million defective parts. In terms of health care organizations, the corresponding goal is to have less than one in a million preventable negative patient outcomes. The concept’s generalization to small medical practices is, however, limited though still useful.
Six Sigma is not merely a goal; it is also a series of methods. A significant part of the Six Sigma approach is to disperse quality control responsibility into a top-down hierarchical structure. Thus, specialists in a particular area oversee the quality control in that area. While the concept originally was meant to apply to manufacturing, it is readily applied to large healthcare organizations, such as hospitals, that are divided up into many specialized areas and functions. Sehwail and DeYong (2003) noted that many of the processes in Six Sigma manufacturing could be applied to large health care organizations. They cited a case study regarding “Mount Carmel’s successful implementation of Six Sigma” (Sehwail & DeYong, 2003, pp. 1, 5). Mount Carmel is a large healthcare provider, and the many discrete and specialized healthcare functions it performs are ideal for overall improvement via Six Sigma.
While Six Sigma methodology has been a proven success in the manufacturing sector, especially with workforce autonomation. It has been debated to what extent it would benefit health care providers. After all, achieving a level of one in a million defective machine parts isn’t the same thing as optimizing patient outcomes in a health care facility. For one thing, even in a huge organization, the sample size is much smaller than for a manufacturer: it would take years for even the largest health care provider to amass a million patient outcomes. Nonetheless, the Six Sigma concept has had great appeal for healthcare administrators: as Chassin (1998) remarked, “Serious, widespread problems exist in the quality of U.S. health care: too many patients are exposed to the risks of unnecessary services; opportunities to use effective care are missed; and preventable errors lead to injuries” (Chassin, 1998, p.565). So even if Six Sigma methods cannot precisely be generalized to healthcare, using them responds to the overall drive for quality in preventing and blunts criticism of suboptimal patient outcomes.
The Lean Six Sigma approach may be best for smaller healthcare organizations. From a statistical standpoint, patient outcomes at small healthcare providers are measured in the hundreds or thousands, not millions, so an approach that acknowledges the differences in the statistical approach desired is best. Koning, Verver, and den Heuvel et al. note that “Healthcare, as with any other service operation, requires systematic innovation efforts to remain competitive, cost-efficient, and up-to-date” (Koning et al., 2006, p. 4). Therefore, any healthcare organization can benefit from Six Sigma implementations, though Lean Six Sigma may be best for smaller ones.
I have not had direct personal experience of Six Sigma implementation. However, it seems obvious to me that at the small healthcare providers where I have worked, that a rigorous quality control initiative could have helped to lower the incidence of mistakes. In particular, there should be a process of quality control review at each step of the patient care process by each employee involved, not just by supervisors. Any member of the organization should be able to intercede in the patient care process if he/she perceives a care quality problem, and without fear of retaliation or reprisal due to any perceived implied criticism of the one making the error. Any such error made should be viewed as an error by the organization and not the individual.
Chassin, M. R. (1998). Is health care ready for Six Sigma quality? Milbank Quarterly, 76(4), 565-591.
Koning, H., Verver, J. P., Heuvel, J., Bisgaard, S., & Does, R. J. (2006). Lean six sigma in healthcare. Journal for Healthcare Quality, 28(2), 4-11.
Sehwail, L., & DeYong, C. (2003). Six Sigma in health care. Leadership in Health Services, 16(4), 1-5.