Six Sigma, QS-9000 Article Has One Minor Flaw

The article "Linking Six Sigma With QS-9000" (Roderick A. Munro, May 2000, p. 47) has one minor flaw. The author confuses the concepts of short-term and long-term capability.

Although the time frame over which the data were collected can be a major influence over long-term capability (Z.lt), the Six Sigma concept of short-term capability (Z.st) describes the process repeatability over consecutive samples within subgroups, accumulated over all subgroups. It assumes the mean is centered on the nominal of the specification. This is the concept of entitlement, whether measured over a week's worth of subgroups or over two years' worth. It is not intended to be a measure of initial process capability as the author describes it.

Some camps use a measure called Z.lt.est as the estimate of the long-term capability of a new or modified process. The estimate specifies that the period over which the sample data were collected was short, where all external factors (Xs) may not have influenced mean shifts between subgroups. It does, however, take into account the overall process mean drift and shift from a centered condition.

LaGrange, KY 

Author's Response

Mark Motyka's discussion about entitlement is correct; however, he missed the part of the article that discussed the difference between the Six Sigma and automotive methods of using capability. The same thing happened when the automotive industry first released the statistical process control manual that is now part of QS-9000. Many people missed the point that Cp and Cpk should be used on a stable process, while Pp and Ppk should be used on any nonstable process. A nonstable process occurs anytime the process is out of statistical control.

It's interesting to observe how statisticians defend what they were taught as absolute. The word "statistics" means "the science of compiling facts or data of a numerical kind, assembled and classified so as to present significant information." But if you look at any two college statistical textbooks, you will probably find any number of discrepancies. Just look at the long, heated debates among the classical design of experiments, Taguchi and Shainin groups to see this in action.

My article was designed to show how the two groups could come together to form a unified front to management without throwing the baby out with the bath water. I encourage anyone interested in continual and/or process improvement to develop a large toolbox full of knowledge and skills. If you only have a hammer, everything may start looking like a nail.

One last cliché in closing: Please use quality methodologies to improve your professionalism. Otherwise you may someday be labeled as a cowboy shooting from the hip!

Ford Motor Co.
Dearborn, MI 

Reduce Medication Errors By Mistake Proofing

Paul Schyve's article "A Trio for Quality" (June 2000, p. 53) explained how the Malcolm Baldrige Award, ISO 9000 certification and the Joint Commission on Accreditation of Healthcare Organization's standards combined to help a health care organization reduce medication errors. I agree with Schyve that these three quality systems provide a framework for process improvement, but that's not enough. To reduce medication errors in health care there needs to be a greater awareness and use of the concept of mistake proofing.

The Japanese coined the term "poka-yoke," which in English means "inadvertent mistakes to avoid." Japanese auto manufacturers em-braced the concept of not tolerating mistakes due to poor process design, because counting defects as a means of quality control will only assure that the defects continue. Changing processes so that mistakes cannot be made in the first place is the solution to a high incidence of medication errors.

One example of mistake proofing in health care is the pharmaceutical company that changed the packaging of the antibiotic Gentamicin. In the past, this drug was packaged with several doses in one container so it was convenient for the pharmacist. Now, only one dose is packaged per container, thereby eliminating the possibility of an overdose.

To prevent medication errors, I believe that more processes need to be designed in such a way that no mistake can possibly be made. Quality professionals should learn to ask themselves the following: How can the process be changed so that it will be impossible to make a mistake?

The Institute of Medicine's recent report that an estimated 98,000 deaths each year are due to medical errors has caused a review of medication error variance reports all across the United States. At one regional medical center, all variance reports from January 1992 through December 1999 were reviewed, and an error rate of 4 to 6% was calculated for each year. More than 1,300 variance reports were written in that time frame. Add to that the energy expended by the corrective action taken in each incident, and yet after eight years of wasted effort, the error rate had not dropped at all.

Health care must change its paradigm from error detection to error prevention. Error detection (variance reports) must be replaced by error prevention (mistake proofing) to assure quality. Otherwise I fear that, in 10 more years, the error rate will not be any lower than it is today.

Certified quality manager
North Platte, NE

Author's Response

Clark Carboneau concurs that the combination of the Malcolm Baldrige Award, ISO 9000 certification requirements and the Joint Commission on Accreditation of Healthcare Org-anizations' (JCAHO) standards can, in combination, help a health care organization reduce health care errors, including medication errors, by providing a strong framework for process improvement. But he pointed out that this is not enough: The goal and concepts of error proofing must also be introduced and implemented in health care. I agree.

Responding to adverse events--"sentinel events" in JCAHO parlance--by conducting a thorough root cause analysis and using the resulting information to redesign processes in order to avoid future errors is a JCAHO accreditation requirement for health care organizations. But this necessary, after-the-fact approach must be combined with proactive techniques. JCAHO staff recently authored a chapter on proactive error proofing of health care processes.1 JCAHO is now beginning to review processes for a draft standard that would require a proactive risk reduction program in health care organizations. The program is modeled after the concepts of the failure mode effects and criticality analysis (FMECA) that is so well-known to engineers.

As Carboneau states, error detection alone will not reduce errors. It is the use of root cause analyses and proactive techniques such as FMECA that will prevent errors. Their use in health care must be encouraged. After all, one of the oldest ethical imperatives in health care is "primum non nocere" or "above all, do no harm."

Senior Vice President
Joint Commission on Accreditation
of Healthcare Organizations
Oakbrook Terrace, IL


1. R.J. Croteau and P.M. Schyve, "Proactively Error-Proofing Health Care Processes" in Error Reduction in Health Care: A Systems Approach to Improving Patient Safety, Patrice L. Spath, ed. (San Francisco: Jossey-Bass Publishers, 1999).

Some Processes May Inconvenience Customers

The article "Beyond Compliance" (Dennis Arter, June 2000, p. 57) compares compliance auditing to management auditing and provides guidelines for performing effective management audits. I can't imagine how a management audit, as described in the article, can be justified by company leaders who want to improve customer satisfaction. In fact, the word "customer" is not mentioned once in the article.

In light of that, I'd like to offer ASQ members an alternative proposition based on my 10-plus years of lessons learned in process improvement. Your organization should redesign its processes in a manner that enables its employees to tailor the processes to do the customer's job. That's it: Just do the customer's job for him or her.

The primary purpose of a process is not to comply with ISO 9000, satisfy internal corporate reporting requirements or consistently pass audits. A process's primary purpose is to enable external customer counterparts to achieve their business objectives cost effectively. Most employees in your organization have customer counterparts. You may be surprised to discover that your current processes and deliverables actually inconvenience your customers. These same processes probably comply with ISO 9000, satisfy internal corporate reporting requirements and consistently pass audits.

If your corporate leaders focused their process reengineering efforts on reducing internal costs, then your organization missed a unique opportunity to gain a competitive advantage. The total cost to a customer can be reduced with a process that does the job for him or her. Process redesign efforts should seek to reduce or eliminate customer costs and reduce internal costs.

The mainstream process redesign approach's fatal flaw is that it causes an organization to become more efficient at delivering something labor intensive to its customers. Chances are that the organization doesn't even know its customers are frustrated, even if it passes a management audit with flying colors.

San Diego 

Author's Response

You are correct. I made no mention of the customer in my article. Nor did I call out employees, regulators, stockholders or the local community.

However, we seem to disagree on the purpose of quality auditing. I believe auditors must serve the enterprise. Auditing is but one of the tools used by an enterprise to satisfy its needs and those of the many stakeholders. Used effectively, audits will most certainly improve customer satisfaction. They will also improve the bottom line.

Kennewick, WA 

Isn't Quality About Data Analysis?

I thought the quality profession was about fact, data collection and analysis, objective evidence and root cause analysis rather than personal anecdotes that incite the audience to action. Donald Berwick's story (Miles Maguire, "First, Stop Doing Harm," June 2000, p. 6) is more suited for the evening news. Please let me counter with a less moving presentation--my own.

I am a commoner, and I pay my premium to my health maintenance organization (HMO) just like millions of other Americans hoping never to need its services. A few years ago, before it was popular to condemn the health industry, I got my money's worth.

After life saving emergency surgery at my local hospital, I was transported to a major teaching hospital in Washington. After 27 days in the hospital, more transfusions than most of the staff had ever seen and a rare back-to-back endoscopy procedure, I was discharged and have since returned to health, work and all other activities.

I had world renowned people looking after me, performing any procedure I needed, and three weeks in a critical care unit--all for the cost of the lowly HMO. My surgeon told me I was a once in a career case, and the only bill I received for the entire ordeal was a $25 fee for a portable X-ray that my HMO case manager told me not to pay. Why? Because the radiology lab didn't heed the doctor's orders to stop taking X-rays.

I have seen the power of quality at work in the medical profession. I am alive and HIV-free in part because the labs and technicians who collect donated blood followed procedures. What better value could I have asked for from my HMO, my surgeon and the hospital?

My daughter is a nurse in our local hospital. It is the only hospital in our county, and it received Joint Commission on Accreditation of Healthcare Organizations accreditation with commendation during its evaluation. My daughter works in the recovery room, and I always get a smile on my face when she tells me she had a fine day at work. That tells me that a whole lot of people did quality work to make people better.

We can't move away from polarizing political debates until the analysis focuses on data, fact and objective evidence, not personal anecdote.

California, MD 

Editor's Response

First of all I agree that "data, fact and objective evidence" have to be the bases we use for decision making. But I don't think that means there isn't room for anecdotal information in the course of developing and deploying a quality system. Many quality thinkers have emphasized the importance of motivation in accomplishing quality objectives, and humans often respond positively to the motivations that are created in narrative structures.

Of course, it's also true that not all anecdotes are created equal. Some of them may be outliers and some may be highly representative of the underlying data. But, as you say, one must ultimately refer back to the data.

In the case of health care, I think that the data are pretty strong, and they show that our medical system is far from a shining example of performance excellence and that it would benefit from expanded use of quality tools.

This is not to say that quality is absent from our health care system. But unfortunately, at least in my view, policy makers are preoccupied with debating various governmental solutions and are not giving sufficient consideration to the gains that would be attainable through the expanded use of quality tools and methods.

Editor, Quality Progress 

What's the Plan For ASQ's Certifications?

Quality Progress has greatly increased the amount of space given to Six Sigma procedures and certifications over the last few months. With few exceptions, ASQ's comparable certifications are ignored. The May 2000 issue's article about Six Sigma in the automotive industry (Roderick Munro, "Linking Six Sigma With QS-9000," p. 47) and Gene Tomlinson's letter to the editor ("ASQ Needs To Review Its Latest Actions," June 2000, p. 10) both discuss the similarity between Six Sigma and ASQ certifications.

If Quality Progress continues to promote Six Sigma, does that mean that the Certified Quality Auditor, Certified Quality Engineer and Certified Quality Technician programs are slated to become obsolete? If ASQ maintains its current certifications, who will attend?

Two of my company's customers required that some people in my company become Six Sigma certified. My company complied, and several engineers (including myself) were trained as either Green or Black Belts at the customer's facility. Neither customer recognized ASQ certifications.

As a result, I not only pay a maintenance fee for my current certifications, but my company had to pay more than $5,000 per person for Six Sigma training. When I originally took my certification exams, I thought it was a proactive way of documenting my knowledge of and experience with quality tools. Now I wonder if I just wasn't paying enough attention to the bandwagon on the horizon.

So, what plans are there for the current ASQ certifications?


Certification Board Chair's Response

ASQ certifications are far from being ignored. Applicants for our CQA and CQT programs continue to grow, while the CQE program maintains its level of applicants. If anything, our programs are more valuable than ever in providing recognized credentials.

We are introducing two new programs: the certified quality improvement associate and the CQA-HACCP for the food industry. These will provide an avenue into new arenas, such as service industries and health care. We also recognize the market for Six Sigma certification and are currently investigating the possibility of a certification program.

For 32 years, ASQ certification has been a proven method for demonstrating knowledge and skills.

Certification Board chair

May 2000 Issue Is Outstanding

I would like to congratulate the entire Quality Progress staff for its outstanding work on the May 2000 issue. I always find something of interest in the publication, but this particular issue is one I will read over from time to time.

Middlefield, OH 

Congratulations To the 'QP' Team

Prior to December 1999, I used to cut out and file the good articles in Quality Progress. Post December 1999, I no longer need to cut the articles out because more and more articles are collection worthy.

Congratulations to the QP team. Now I maintain entire QP editions and, more importantly, my company has been able to reap performance benefits by implementing the knowledge presented in the articles.

Chandigarh, India  

A Transposed Quote In 'Quality Progress'?

The editor's column in the May 2000 issue of Quality Progress (Miles Maguire, "What's Good for ... ," p. 6) quoted Charles Wilson as saying, "what's good for General Motors is good for the country." This quotation was transposed years ago to malign GM. Wilson actually said, "What's good for the country is good for General Motors."

Cupertino, CA 

Editor's Response

According to my research, the quote is accurate--it's just not the complete quote, which was as follows: "What is good for the country is good for General Motors, and what's good for General Motors is good for the country."

I've also seen references to the quote as "What's good for the country is good for General Motors, and vice versa."

I agree that the quote is sometimes taken out of context to malign GM, but as I noted in my column, what Wilson spoke was the plain truth at the time.

Editor, Quality Progress 


A table and figure that accompanied the article "Putting Taguchi Methods to Work To Solve Design Flaws" (James O. Wilkins Jr., May 2000, p. 55) contained errors. In Figure 2, the arrow with the phrase "output response" should have been reversed so that it pointed to the right. In Table 1, the boxes containing S1 and S2 should not have appeared.

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