By Louise Lazear

WestgardJames O. Westgard, Ph.D.

In today’s business landscape, producing a quality product or service while meeting customer needs, reducing operational costs and staying in the black is more difficult than ever. Why hasn’t someone developed a recipe for business success that everyone can follow?

Someone has. In fact, many people have. Numerous quality improvement strategies, developed and implemented for industry, have found their way into healthcare and the clinical laboratory. Spurred by rising costs, ceilings on reimbursement and a critical shortage of trained personnel, many clinical laboratorians are looking for just such a recipe or process. For many, Six Sigma, a fact-based process-excellence initiative, has improved quality and reduced costs.

Six Sigma process is well documented
The popularity of Six Sigma’s process excellence approach is well documented. Industry titans such as General Electric, Black and Decker, Allied Signal/Honeywell and Johnson & Johnson are among the name-brand companies that attribute their success to Six Sigma principles.

According to those who have gone through the process, if Six Sigma principles and ideals are to take hold in a company, they must be supported and demonstrated from the CEO on down. This top-down integration of Six Sigma concepts into a corporate culture along with linking improvements to employee financial compensation has earned Six Sigma its reputation for success. Because of their successes, companies such as GE and Johnson and Johnson along with its subsidiary Ortho Clinical Diagnostics, offer their Six Sigma expertise to other companies on a consultative basis.

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Chart: Six Sigma Quality Design & Control

It started in manufacturing
Six Sigma was initially implemented by manufacturing engineers at Motorola in the mid 1980s to cut waste and improve quality. The process is based on a statistical evaluation of the number of defects per million opportunities (dpmo) in any given process, with the goal of reducing defects through continuous process improvement. In statistical terminology, sigma is defined as the standard deviation, or precision, of a process. A Six Sigma performance goal for any process means that errors are so few that six standard deviations of the process will fit within the quality limits required for that process (see below). “Sigma-metrics” converts error rates to sigma values: an error rate of 317,400 dpmo is equivalent to a one sigma process; an error rate of 2,700 dpmo equates to a three sigma process; and an error rate of 0.002, or better than 99% perfection, equates to a Six Sigma process. Realizing that adjustments must be made for measurement of the normal distribution of any process over time, Six Sigma practitioners typically quote sigma-metrics with a 1.5-sigma shift, resulting in more liberal error rates than the “centered” metric discussed above. As a result, the benchmark for “world class quality,” or Six Sigma performance, is conventionally measured at 3.4 dpmo. To provide some perspective, most businesses, including laboratories, perform at levels of about four sigma, or 6,210 dpmo, and improving processes to a level of five sigma, or 233 dpmo, is often a first goal in a Six Sigma process.

Distinctive nomenclature
A distinctive nomenclature and series of core concepts are central to Six Sigma. For example, while Total Quality Management (TQM) identified organizational leaders and team facilitators as leaders and members, Six Sigma adopters are known as champions, master black belts, black belts and green belts as they implement the process within an organization.

Champions are top-level executives who can promote initiatives across divisional boundaries, often spearheading a company-wide change in organizational culture. The real ground troops, however, are the black belts, highly visible employees who undergo extensive training in statistics, problem analysis, process management and interpersonal relations. Becoming a black belt is no easy task, requiring upwards of four weeks of training, certification and the completion of one or two Six Sigma projects. Most black belts within organizations eventually return to management (albeit with promotions), but some go on to become masters who train and mentor other black belts. Green belts are typically middle managers that continue conventional duties while participating in Six Sigma projects.

Also involved is a series of formal steps from inception to completion. Perhaps the most crucial of these is the identification and prioritization of projects within the organization. Initially, many companies select projects that are known to require immediate attention or that directly impact customer service. The second phase requires the measurement of key product characteristics, including process parameters and performance. Third, the collected data must be analyzed to determine where improvements can be made. Lastly, improvements are initiated, and the process is controlled through a rigorous program of continual monitoring and feedback.

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Can Six Sigma work in the clinical lab?
Can Six Sigma be used to improve quality and reduce costs in the clinical laboratory? Absolutely, according to James O. Westgard, Ph.D., professor in the department of pathology and laboratory medicine at University of Wisconsin Medical School, president of Westgard QC and author of Six Sigma Quality Design and Control, a manual that defines the process labs use. In fact, the lab’s existing quality control procedures and abundance of data make it well suited to the Six Sigma initiative.

“Six Sigma is very simple to do with analytical processes compared to other healthcare processes,” said Westgard. “We have standardized processes, we know the variation or can predict the variation, and we know essentially what the sigma performance is.”

Westgard’s approach to Six Sigma targets the analytical process itself, with the goal of reducing false rejection rates and increasing error detection by applying the right amount of quality control on a test-by-test basis. Although the ultimate goal is to achieve the quality necessary to meet customer requirements, Six Sigma reduces the measurable internal costs associated with repeat runs, the unnecessary use of multiple controls and the external costs to the healthcare system caused by laboratory errors.

Focus on high-volume, automated processes
To implement a Six Sigma process, Westgard suggests that managers initially focus on high volume, automated processes where improvements can have the greatest impact. The first step includes measuring the performance of various processes with data available from existing QC procedures. The second step is to define tolerance limits and convert process performance to sigma-metrics. Although this step requires a basic understanding of statistics, there are tools and training to assist laboratorians in this process. QC data can be reflected in sigma values by using published benchmarks, including CLIA regulations and other standards. For example, cholesterol testing has a 10 percent allowable total proficiency testing event error as established in CLIA.

Conversion of this specification to sigma-metrics is accomplished by dividing this value (10 percent) by five and by six to obtain five sigma and six sigma precision respectively. Therefore, to operate at five and six sigma levels, cholesterol analysis must be performed with two percent and 1.7 percent proficiency testing respectively. Since many laboratories consider CLIA regulations “acceptable,” setting goals to attain five and six sigma performance levels leaves room for improvement.

After evaluation of the process performance, each test must be assessed for quality control. For example, processes with high performance may be performed with lower quality control, including wider control limits, which can reduce false rejection rates, saving time, money and effort. Processes with low performance must go to higher levels of quality control, involving more complex procedures that ultimately can reduce false rejection rates and their associated costs. This approach to process

improvement may appear arduous and statistically challenging, but according to Westgard, it also provides a template under which quality can be guaranteed. “We are essentially fitting tools and techniques that we have developed over the last 10 years into the Six Sigma framework. That is the difference from what you encounter in other organizations and industries.” (For more information on Westgard’s techniques and experiences, visit

Ortho Clinical assists West Tennessee Healthcare
While Westgard’s approach is to focus on the analytical aspects of laboratory services, others use Six Sigma techniques to address efficiency and productivity. Leo Serrano, administrative director of laboratories for West Tennessee Healthcare, turned to Ortho Clinical Diagnostics (OCD) to assist his lab. Spurred by rising costs, low reimbursements and a dearth of qualified personnel, Serrano and OCD’s ValuMetrix team performed a rigorous analysis of his laboratory’s workflow, resulting in the eventual automation of the chemistry and immunochemistry areas of the central laboratory.

Serrano learned about Six Sigma at a seminar last year and took the concept back to senior management for approval. To assist with process implementation, OCD consultants were retained to identify Six Sigma target processes, train green belts and assess performance. However, much of the work fell to Serrano and two associates. Since initiating Six Sigma, his team has standardized in-lab turnaround time and begun focusing on the ER, including an analysis of collection times and how results are transmitted back to the department. “Six Sigma helped us change the way we look at our processes …and it has helped us control costs. Over the years, we have significantly reduced our operating costs for supplies and equipment. Therefore, if I can improve my processes so that I avoid duplication and improve productivity, then I have succeeded in reaching the two major goals of my organization: improving quality and reducing costs.”

The power of a Six Sigma initiative is that it can be used to improve almost any process in healthcare, from admitting to pharmacy orders and billing. For laboratorians, reducing costs and improving quality are no longer mutually exclusive. Since our business is to collect, analyze and produce data, the laboratory may be the most logical healthcare setting to initiate Six Sigma.

The hurdle for many will be in convincing peers and administrators that a Six Sigma initiative is worth the considerable effort. However, the arguments in favor seem to pile up quickly. After all, what’s the downside of a process that improves quality, reduces costs and throws in martial arts training as a bonus. This crouching tiger may be the answer to many of the laboratory’s not-so-hidden dragons.

Louise Lazear is a freelance writer in Charlotte, N.C.