Analytics · Method validation

About the Method validation category

Analytics › Method validation stability-indicating method linearity LOD & LOQ

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KLindqvistTL4 Moderator14 Jun 2025#1

Community wiki post. Any member at trust level 3 or above can edit this post; every edit is recorded. Last edited by hana.sato on 31 Jan 2026.

12 Jul 2025 — KLindqvist: Restructured into sections so the outline is navigable.
18 Sep 2025 — mira.patel: Added the limitations paragraph that review asked for.
31 Jan 2026 — hana.sato: Corrected an arithmetic slip in the second example.

Editors: KLindqvist, mira.patel, hana.sato

Staff post. Actions described here are recorded in the public moderation log and may be challenged in Meta.

Specificity, linearity, precision, accuracy, robustness, system suitability, and why two labs disagree.

This post is a community wiki: any member at trust level 3 or above can edit it, and every edit is recorded with its author and a note. If the scope described here has drifted from what actually gets posted, edit it rather than starting a topic about it.

What belongs here

Questions specific to method validation, with the units and the context stated.
Reports and datasets, with the collection method stated.
Disagreement about the substance, conducted in public.

What belongs elsewhere

Anything urgent belongs in Safety, immediately, and not here.
Anything about how this site works belongs in Meta.
Requests for a maintained page belong in Wiki requests.

Before posting, it is worth checking the documentation commons and this category's tag pages. A great deal of what gets asked here has a maintained answer with a review date on it, which is more reliable than a two-year-old reply.

0 likes 13mo

t.vasquezTL4 Moderator26 Aug 2025#2

Staff post. Actions described here are recorded in the public moderation log and may be challenged in Meta.

Moderation notes for this category, so that nothing about how it is run is a surprise.

Topics get moved into and out of here regularly. A move is not a judgement — the category tree is not obvious from outside and putting a question in the wrong place is expected. When I move something I say so in the topic and the action appears in the public log with the guideline cited.

The two guidelines that come up most often in this category are R2, on supplying a source when asked, and R7, on category placement. Neither is used punitively.

1 like 11mo

p.amankwahTL2 Moderator18 Oct 2025#3

As a member rather than staff: the most useful thing I did when I started reading this category was to work through the tag pages rather than the topic list. The topic list shows you what is recent. The tags show you what is settled.

10 likes 9mo

k.agyemanTL2 Moderator3 Dec 2025#4

Suggestion for the wiki post above: it would be worth linking the two or three most-referenced topics in this category directly, since new members reliably ask for exactly those. Happy to make the edit myself if nobody objects, with a revision note.

23 likes 8mo

j.vogelTL2 Moderator16 Jan 2026#5

Why two laboratories may disagree: after validating the same method, they may still report different purity on the same sample due to integration differences, column age differences, subtle differences in mobile phase pH or temperature. This is normal and not a sign that one is wrong.

32 likes 6mo

TL4_HalvorsenTL4Leader · Journal club26 Feb 2026 · edited#6

On post #2 — agreed on the reasoning, with one qualification.

Specificity: the method can distinguish the intended compound from related impurities and degradation products. Tested by comparing results on pure compounds, mixtures of compounds, and degraded samples.

0 likes 5mo

This topic was referenced in

Repeatability versus intermediate precision — what changed sinceAnalytics › Method validation · 4 replies

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