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Westgard Rules

How Kanta applies Westgard multi-rule QC to your data.

Kanta applies Westgard multi-rule QC automatically when you submit a QC run. You do not need to evaluate rules manually — Kanta flags which rule(s) were violated and whether the run is a warning or a rejection.


The rules Kanta applies

RuleDescriptionAction
1₂sOne value exceeds ±2 SDWarning — investigate but do not reject
1₃sOne value exceeds ±3 SDReject — do not release patient results
2₂sTwo consecutive values exceed the same ±2 SD limitReject
R₄sTwo consecutive values span more than 4 SD (one above +2 SD, one below −2 SD)Reject
4₁sFour consecutive values exceed the same ±1 SD limit on the same sideWarning
10xTen consecutive values on the same side of the meanReject

How Kanta displays rule violations

After submitting a QC run, the result row shows:

  • Pass — all Westgard rules satisfied
  • ⚠️ Warning — a warning rule triggered (1₂s or 4₁s); investigate, consider running QC again before releasing results
  • Reject — a rejection rule triggered; do not release patient results from this analyser; corrective action required

Click the violation badge to see exactly which rule failed and for which parameter.


Multi-level QC

Kanta evaluates Westgard rules across all QC levels simultaneously. A 2₂s violation can be detected across two different control levels (e.g. Normal and Abnormal High both drift in the same direction) — Kanta catches this and flags it accordingly.


Configuring which rules to apply

By default, all standard Westgard rules are active. Lab Managers can configure which rules to apply per analyser:

  1. Go to AdminLab Sections → select section → Analysers
  2. Click the analyser → QC Settings
  3. Toggle individual Westgard rules on or off
  4. Set whether 1₂s should be a warning or a rejection for your laboratory's policy

For help, contact your Lab Manager or email [email protected].