The Westgard Rules

What's New on Westgard Web: December 2011

Posted by Sten Westgard, MS

THE QUALITY OF DIABETES TESTING IN 2011

Dr. Westgard participated in the Top of Diabetes Symposium in Zwolle, Holland. This special conference tackled not only harmonization, standardization, biologic variability, and tight glycemic control.

How good are our HbA1c methods?
http://www.westgard.com/the-quality-of-diabetes-testing-2011.htm

IT'S OFFICIAL: EQC IS OUT AND QC PLANS ARE IN

The CLIA Final Rules of 2003 put into place a set of scientifically unsound practices known as Equivalent QC. For years, CMS has been seeking a solution to the problem. Now that CLSI has published EP23A, a guideline for Risk Analysis and QC Plans, is the future based on risk?

Read the CMS memo on Lab QC based on Risk Management
http://www.westgard.com/official-risk-qc.htm

 

DOES THE TOTAL BRAIN-TO-BRAIN LOOP ALLOW ROOM FOR ANALYTICAL ERROR?

A popular concept of the moment is to talk about the Brain-to-Brain loop in laboratory medicine. But does that concept mean we should stop thinking about the allowable error in our analytical methods? Can our brains handle more than one idea at a time?

When we talk about Total Analytical Error, doesn't that mean we're talking about the analytical process?
http://www.westgard.com/brain-to-tea.htm

 

A RISK ANALYSIS EXAMPLE: HFMEA FOR SPONGES

Failure Mode and Effect Analysis (FMEA) is the most common tool associated with Risk Analysis. As we move toward a time when Lab QC will need to use Risk Analysis, it's useful to review examples of how FMEA is used in other healthcare processes.

How many ways can a sponge fail?
http://www.westgard.com/hfmea-sponges.htm

An Advisory on Blood Glucose Meters

Posted by Sten Westgard, MS

[Hat-tip to the AACC Point-of-Care listserve, which first posted a notice about this article]

The Pennsylvania Patient Safety Advisory has a regular electronic newsletter highlighting new science and studies about healthcare safety. Their December 2011 issue has a particularly interesting article for laboratory testing:

Point-of-Care Technology: Glucose Meter's Role in Patient Care, Lea Anne Gardner, PhD, RN, Senior Patient Safety Analyst, Pennsylvania Patient Safety Authority.

This review examined more than 1,300 reports of glucose-meter problems from the Pennsyvlania reporting system database from 2004 to 2011. Of those reports, 71 near-miss or adverse event reports occurred. Most intriguing are the report excerpts directly quoted in the study. Of those reports, 72% of the near-miss or adverse events occurred with high-blood glucose results. That is, where the glucose meter had a sudden high value that may or may not have been reflective of the actual patient's clinical state. For example:

"A patient's blood sugar was checked using a [glucose meter]. The lunchtime result was 517. A [blood glucose test] was [immediately] retaken to check for accuracy, and the result was greater than 600. A blood [laboratory] test was conducted per protocol, and the [lab] glucose [result] was 136..."

What do you think happened next?

Six Sigma in the Lab literature

Posted by Sten Westgard, MS

The most recent issue of Clinical Chemistry and Laboratory Medicine has an article on Sigma-metrics:

Practical application of Sigma Metrics QC Procedures in clinical chemistry, Christian HH Schoenmakers, Andre JM Naus, Henricus J Vermeer, Douwe van Loon and Gerard Steen, Clin Chem Lab Med 2011;49(11):1837-1843.

This study shows how a group of laboratories not only used Sigma-metrics to assess their chemistry tests and optimize their QC procedures, but also generated a table linking specific Sigma-metrics to the appropriate QC procedures.

One interesting finding is that, in a table showing the performance of 4 laboratories with the same instrument, the Sigma-metric results based on imprecision alone were very consistent. For example, if the Sigma-metric of CK for Lab 1 was 19.4, the other three labs had Sigma-metrics of 20, 19, and 18.8. And if the Sigma-metric for Total protein for Lab 1 was 2.4, the other three labs had Sigma-metrics of 2, 3, and 2.3. When bias was factored in, the difference between the Sigma-metrics of the laboratories grew larger, however.This tells us that instrument performance - as we hoped - is pretty consistent from instrument to instrument. However, it appears that there are bigger differences from lab to lab, which is reflected in their different bias values.

Another interesting part of the study is the included list of trouble-shooting actions. Every laboratory knows how to run QC, but once there is a real out-of-control situation, the guidelines on what to do next are not quite as helpful. The list of questions generated by the study include not only analytical considerations, but some practical issues of the lab and instrument:

• "Does the alarm concern one or more tests carried out on the same instrument?"
• "Is it a first alarm, or it it one in a series of alarms?"....
• "Is the correct QC material used?"
• "Is the QC material expired?"
• etc.

This study is an expanded discussion of findings that were first published in a poster at the 2010 Quality in the Spotlight conference, then later published on Westgard Web: Saving money by applying TEa and Six Sigma for internal QC.

Again,the full study is worth reading, not only for its Roadmap of Sigma-metrics to QC rules, but also for the in-depth discussion of the use of Sigma-metrics.

Nine Questions about Risk-Based QC Plans

Posted by Sten Westgard, MS

Now that we know EQC will officially be phased out and instead Labs will have to develop QC Plans through Risk Analysis (as explained in CLSI's new guideline EP23A), some of the waiting is over. EQC, which was fatally flawed from the start, is going to go away.

However, the exact regulations about QC Plans and Risk Analysis have yet to be written (or, at least, are not yet known by the general public). What makes this more uncertain is that EP23A is only meant as a guideline, and the Risk Analysis approach discussed in the guideline is only meant as a possible example. Risk Analysis is a long-established technique (outside the medical laboratory) and has many different formats and levels of complexity. Even between EP18 and EP23, there are discrepancies between the Risk Analysis recommendations (EP18 recommends a 4-category ranking of risk, while EP23 recommends a 5-category approach).

So while we're waiting for the other shoe to drop (in the form of detailed regulations and accreditation guidelines governing Risk Analysis), we might as well talk about what questions those rules will have to answer...