Posted by Sten Westgard
One of the highlights for me of the AACC convention in Washington, DC, was my inclusion in a poster that analyzed the method performance of the Abbott Architect c8000. I'm pictured here with fellow authors (left to right) Gene Osikowicz, Charles Wilson, and John Baker (lead author). They deserve most of the credit for the work of collecting the data.
The poster can be viewed here and the QC application on Westgard Web can be viewed here. -----
Posted by Sten Westgard, MS
We got the following question emailed to the website recently:
Greetings, I was [wondering] if the following case represents [violation] of 4 1s rule?
Control (A) point 1= EXCEEDS 2 SD /-2 SD lines >> warning
Control (A) point 2= WITHIN 2 SD/-2 SD lines >> accepted
Control (A) point 3= EXCEEDS 2 SD /-2 SD lines >> warning
Control (A) point 4= WITHIN 2 SD/-2 SD lines >> rejection
all the point[s] on the same side of the mean.
What do you think? The answer, after the jump
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Posted by Sten Westgard, MS
An interesting question came in through email (
"1. Can we apply Westgard multirules to hematology control?
2. I read in one paper that the hematology control range is calculated as mean +/- 2.5 SD, is this correct and if not how can I calculate own laboratory hematology control range?"
The answer, after the jump...
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Posted by Sten Westgard, MS
Posted by Sten Westgard, MS
An interesting question came from one of our readers, about how to interpret certain outliers.
So let's take one example, just two control values, expressed in z-scores. If the low control is -3.1 and the high control is + 2.3, which rule is violated? the 1:3s rule? The R:4s rule? Both?
An answer, after the jump...
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Posted by Sten Westgard, MS
An important new study was published in the International Journal of Laboratory Hematology, on the QC practices of coagulation laboratories.
But here's a question for you: of all these activities, how many of them occur greater than 90% of the time - and which one doesn't?
- Repeat the QC, and if it passes, report results
- Open [and run] new QC
- Look for trending
- Discontinue testing until controls are within limits
- Repeat all patient samples from the last acceptable QC
To find out which one of the activities occurs at a frequency not like the others, follow the jump...
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Visit our booth or better yet Thermo Scientific's booth for a nice take-home from Chicago.
Posted by Sten Westgard, MS
Posted by Sten Westgard, MS
Posted by Sten Westgard, MLO
In the November 2012 MLO magazine there is an intriguing article by Roy Midyett, a hematology supervisor, titled "Empty QC"
Here's how Mr. Midyett defines "Empty QC":
"Empty QC is any nominal QC that does not give techs performing the test any more confidence than they would have without the QC, and has by logic or experience, no influence on the reporting of the test."
Is Mr. Midyett correct? Have our QC procedures become meaningless gestures? More after the jump.
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Posted by Sten Westgard, MS
So here's a Normalized Method Decision chart for a cholesterol method.
Which method would you choose?
Posted by Sten Westgard, MS
Posted by Sten Westgard, MS
Recently, a user submitted a question about the mandatory use of the 10x rule on chemistry analytes as mandated by ISO 15189 through NABL:
"Specific criteria of accreditation of NABL India (for ISO 15189) say that 10x should be considered as a violation for clinical chemistry and Immunoassay parameters. However we understand that Westgard rules consider it as a warning only. Please advise."
So, the central question is, does ISO 15189 mandate the use of the 10x control rule?
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