Posted by Sten Westgard, MS
In the recent issue of Clinical Chemistry, an editorial reviews the current state of Vitamin D testing: "There is common agreement that 25-OHD is a 'difficult' analyte."
25-Hydroxyvitamin D: A Difficult Analyte, Graham D. Carter, Clin Chem 58:3; 486-488 (2012).
At the same time, the editorial notes that marked process is being made:
"Nevertheless, results submitted to the international Vitamin D External Quality Assessment (DEQAS) have shown a gradual reduction in interlaboratory imprecision (CV) in recent years - from >30% in 1995 to 15% in 2011."
The question is, is that reduction in imprecision good enough? Or is the quality required by Vitamin D still too "difficult"?
More after the jump...
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Posted by Sten Westgard, MS
So we all know that Risk Analysis is coming to laboratories in the US. (click here if this is news to you). But Risk Analysis, particularly the FMEA technique (Failure Mode and Effects Analysis), is not new to healthcare. Outside the laboratory, plenty of healthcare practitioners have been performing FMEA.
So what do they think about this technique? Try and guess which one of these responses is from a someone in healthcare:
- "The jury's still out on the FMEA process because... has anybody evaluated FMEA as a tool for analysing risk? And it turns out there isn't... well why are we doing this process?... When all it is doing is bringing a few things to the surface, which is no bad thing, but it's not a validated process."
- "...Forget FMEA. It doesn't really work effectively, I don't think, and the scores are a hindrance rather than anything else, year... We wasted a lot of time on FMEA before we realized, this isn't actually working. Yeah, because I think you can get caught up on just the score, that's the thing."
- "The scoring in the FMEA teams need to be the same people, if you change half way through because of the highly subjective interpretation things change dramatically."
Posted by Sten Westgard, MS
In the December 2011 issue of Point of Care journal, an interesting study was published:
Preanalytical Errors in Point-of-Care Testing: Auditing Error of Patient Identification in the Use of Blood Gas Analyzers, Natalie A Smith, David G Housley, Danielle B. Freedman, Point of Care, Volume 10: Number 4, December 2011.
The study looked at patient identification errors on a blood gas analyzer in various departments in a hospital. Bearing in mind that this is just one type of pre-analytical error, what do you think the rate was? Given around 100,000 tests, what would you guess as the number of defects?
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Posted by Sten Westgard, MS
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?
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Posted by Sten Westgard, MS
A recent Clinical Laboratory Strategies article:Anchoring POC Quality in Clinical Decision-Making and the related study: Novel analysis of clinically relevant diagnostic errors in point-of-care devices, KM Shermock, MB Streiff, BL Pinto, P Kraus, an dPJ Pronovost, (J Thromb Haemost 2011;9:1769-1775) have an interesting observation about the use of the correlation coefficient to accept method performance.
They looked at Hemochron POC devices, analyzing 1518 paired INRs. The correlation between the POC and laboratory measurements ranged between 0.84 and 0.91.
The authors stated, "Traditional, quarterly, quality assurance studies emphasize correlation analysis." So this study has good news, right?
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A new study in Clinical Chemistry investigated the errors rates for Point-of-Care (POC) devices:
Can you guess what the error rates were?
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Posted by Sten Westgard, MS
While we recently got a study that estimated the (frightenly high) number of Adverse Events caused by US hospitals, it looks like other countries are not content to let us stand alone. Now Sweden is doing us one better. Guess what the Adverse Event rate is in one hospital in Sweden?
- 28.2%
- 20.5%
- 6.3%
- 3.32%
Which number would you choose?
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Posted by Sten Westgard, MS
Posted by Sten Westgard, MS
Posted by Sten Westgard, MS
Posted by Sten Westgard, MS
Posted by Sten Westgard, MS
I was looking over a recent study of a compact blood gas analyzer conducted over multiple sites, multiple cartridges, multiple days, etc. In other words, this was a study that was doing a very thorough job.
Then I reached a section where suddenly it all fell to nonsense: measurement uncertainty.
So they calculated measurement uncertainty, but then they compared the results against Ricos desirable imprecision performance specifications.
Huh?
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Posted by Sten Westgard, MS
In Biochemia Medica, a recent article detailed the Minimum requirements for the estimation of measurement uncertainty:Recommendations of the joint Working group for uncertainty of measurement of the CSMBLM and CCMB.
Can you guess how many?
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Posted by Sten Westgard, MS
Posted by Sten Westgard, MS
Posted by Sten Westgard, MS