Q: "You mentioned that there can be variation in performance even with different reagent lots. Are you recommending that we change QC rules based on the performance of each lot on each instrument?" This is another question from our Cut Your QC webinar, now available as an on-demand recording. https://us02web.zoom.us/webinar/register/WN_F5IRlqySRR6e...

I came across a rare but intriguing study of measurement uncertainty recently:Standardized Estimation of Measurement Uncertainty in Clinical Chemistry Using ISO 20914. Mohammad I. Ahmad, Fayha S Ahmed, Deepa Rao, Mohamedi Begum, Sheifa Joan. Clin Lab 2026;72:1-6. https://www.clin-lab-publications.com/article/5788The study looked at 27 general bioch...

I read a recent paper on errors across the Total Testing Process (TTP) recently. It's a unique paper, one that delved into the types of non-conformances.   Evaluation of Non Conformances in the Total Testing Process of a NABL-accredited Clinical Biochemistry Laboraotry: An Observational Study. Dharmikkumar Savjibhai Patel, Harshkumar Darj...

"Can this approach [Cut Your QC] be used on QC for Point of Care devices? Are rules built into these devices that can't be modified like standard central lab instruments?"This is another question from our Cut Your QC webinar, now available as an on-demand recording. https://us02web.zoom.us/webinar/register/WN_F5IRlqySRR6eRcrm9Zz9mQThe questioner sa...

"We have a 1:3s rule to reject on one level, but 2 other levels are within 1 SD. Staff is just repeating the 1:3s. Is that the right approach? Also, do you apply rules across materials?" [Another question from the Cut Your QC webinar, now available as an on-demand recording: https://us02web.zoom.us/webinar/register/WN_F5IRlqySRR6eRcrm9Zz9mQ  ]...

"What is the solution if the quality control comes with 2 SD, do we need to change the product to a 3 SD control?" Another question from our Cut Your QC webinar, still available on demand at https://us02web.zoom.us/webinar/register/WN_F5IRlqySRR6eRcrm9Zz9mQ I believe this question is referring to the range that comes with the control. The manufactu...

Another question from the Cut Your QC webinar: "Most of my staff are generalists. It can be difficult for them to keep up with all of the details in every department. If we use different QC rules on each assay and instrument, how do we manage their frustration and confusion?" I get it. The prospect of every assay having a different set of QC rules ...

A follow-up question to one of the earlier Q&As: "If multiple laboratories observe a stability-related drift in a control material before the end of the manufacturer's claimed shelf life, shouldn't this trigger a reassessment of both the assigned target values and the validated stability claims by the manufacturer? "From my perspective, if real...

Another question from the Cut Your QC webinar in September: "How do we account for issues with the controls themselves (i.e. real life stability is shorter than manufacturer's recommendation)?" Of course, this is the nightmare of the QC professional: if the controls introduce more variability, the signals from QC are not completely reflective of th...

Another question that came up in our Cut Your QC webinar last month: "If a lab is repeating QC until the QC "passes", must all the out-of-control QC be recorded in the LIS? Should they be marked as accepted or rejected?" If you take an action during troubleshooting, or during any step of your laboratory operations, you should record it. To selectiv...

Another question from our Cut your QC webinar: Do accreditation bodies accept the Six Sigma metrics? Let's start out by being clear: Six Sigma is NOT required by CLIA, CAP, JCI, or any other regulatory or accreditation system in the world, as far as we know. It is an option, not a mandate. Thus, it's not something that has to be accepted. But it sh...

Another timely question from our Cut Your QC webinar 9/25/26: "What model can be used with planning QC based on the clinical risk to the patient, as considered ISO 15189? One of the challenges lies in selecting quality specifications – specifically, how to determine whether the approach is too lax or too strict." Risk-driven, Risk-focused, Risk-cen...

We got a lot of questions during our Cut Your QC webinar, too many to answer during the session. So here's one that we didn't get to "In the evening I run one level of QC and it fails 1:2s. Do I need to rerun?" This is a curious question. QC results are not different depending on the time of day. A 1:2s in the morning is the same as a 1:2s at night...

As we prepare for our Cutting Your QC webinar, we've gotten nearly two thousand registrations, along with a lot of questions. https://us02web.zoom.us/webinar/register/WN_F5IRlqySRR6eRcrm9Zz9mQ The most common question we're getting is, What does "Cut your QC" mean? I believe this comes from a perspective of many labs, that QC cannot be reduced...

Over the past few months, I've gained a bit of a reputation as a LinkedIn grouch. When I come across posts here that describe the Westgard Rules, analytical Sigma metrics, QC in general, I am quite direct about pointing out errors. In the flood of AI-generated images and flyers, there is currently an overwhelming trend to get things wrong. Over the...

More than 600 of your laboratory peers are already registered for Cut Your QC. https://us02web.zoom.us/webinar/register/WN_F5IRlqySRR6eRcrm9Zz9mQ Now there are some qualifiers, of course. Not every lab nor every instrument is going to be able to reduce QC. A badly engineered instrument. Or a poorly maintained and deteriorating instrument. Or a poor...

An Indonesian study in Diagnostics attempted to make a comparison between Siemens and Roche instrumentation using Peer Group Sigma metrics. Out of 30 assays, Roche won 29 of 30. I can't say I wholeheartedly agree with the methodology of the study: peer group data can obscure what individual laboratories experience. The details can get lost in ...

Like many authors, I keep track of where I'm cited. So I was a bit surprised to see I had been referenced in a paper in the Agricultural Association of Textile Chemical and Critical Reviews Journal: https://doi.org/10.21276/AATCCReview.2026.14.03.22 Not the usual journal I expect. But even more curious, the title of the paper is "An overview of qua...

After premiering this event at ADLM, we are opening it up to everyone through zoom. Please join us September 25th, at 11 am central standard time. At last, a frank look at why we need to do less QC, and how we can make those reductions safely.  If you enjoy being out of control every day, if you get a thrill every time you have to repeat a con...

"I have a question about establishing a Levey-Jennings control chart. laboratories should collect a minimum of 20 measurements over at least 10 days to calculate the mean and SD for the chart. My question is: Is it required that these initial 20 data points must fall within the manufacturer's declared range (or assigned values) for the control...