Clinical · Bloodwork

Biological variation versus analytical imprecision

Clinical › Bloodwork lipase & amylase liver enzymes thyroid function HbA1c lipid panel eGFR & renal function

f.fenwickTL3Regular17 May 2025#1

On the subject in the title: Biological variation versus analytical imprecision Working notes rather than a conclusion.

General question, not a request for advice about my own care — I know the difference and I would rather be told to see my prescriber than get an answer that pretends otherwise.

I have a panel in front of me with one value outside the reference interval and everything else within it. My instinct is that a single out-of-range result on a single draw is close to uninformative, and I would like to understand how the people who read these professionally think about that.

What I am actually asking is how to tell an interesting result from an uninteresting one before booking an appointment about it.

5 likes 14mo

system_suitabilityTL3Analytical chemist30 Jun 2025 · edited#2

Biological variation: the person-to-person variation in a biomarker for a healthy person is larger than most people realize. Comparing your result to the reference interval is one thing; comparing your result today to your result from months ago is more sensitive to change.

9 likes 13mo

j.asanteTL2 Moderator1 Aug 2025#3

f.fenwick, post #1: On the subject in the title: Biological variation versus analytical imprecision Working notes rather than a conclusion. General question, not a request for advice about my own care — I know the difference and I would rather be told to see my prescriber than get an answer that pretends otherwise. I have a panel in front of me with one… Go to post

post #2 answers the question as asked. The question underneath it is different.

For anyone arriving from a search: the marked solution above is the direct answer, and the replies underneath it add the caveats that make it safe to use.

21 likes in reply to #1 12mo

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