This guide describes the step-by-step process for creating, logging measurements and evaluating quality control (QC) samples. Control samples, per ISO 17025 §7.7.1, are used to ensure the reliability of analytical results.
Before you begin, make sure the following data exists:
| # | Prerequisite | Why it's needed | Page |
|---|---|---|---|
| 1 | Analytical Instruments | Each control sample must be linked to the instrument on which the measurement was performed. Without an instrument, a record cannot be created. | Instruments |
| 2 | Lab Methods | The analysis method is required — it determines which acceptance criteria apply. | Lab Methods |
| 3 | Analysis Elements | Needed when logging measurements (results) on the control sample. | Elements |
| 4 | Acceptance Criteria | Define expected value and acceptable limits for each method–element combination. Without these, limits are not auto-populated and the "Pass/Fail" evaluation is unreliable. | Acceptance Criteria |
Tip: The creation order should be: Elements → Lab Methods → Instruments → Acceptance Criteria → Control Samples.
Go to the Control Samples page from the QC menu. A table of existing control samples is displayed.
The visible table columns are:
| Column | Description |
|---|---|
| Document No. | Unique code (for example QC-YYYY-0001) |
| Control Type | Blank, Duplicate or CRM (Certified) |
| Date | Date the test was performed |
| Instrument | The analytical instrument |
| Lab Method | The laboratory method |
| Batch No. | Reference material batch number |
| Status | Pending, Pass or Fail |
Click the "+" button on the toolbar to open the creation form.
Fill in the fields:
QC-YYYY-0001) or enter your own codeAfter saving, open the control sample in edit mode. Below the basic fields, the "Measurement Results" section appears.
Click "New Measurement" and fill in:
| Field | Description |
|---|---|
| Element | The chemical element or parameter |
| Measured Value | The value measured |
| Expected Value | The reference value (auto-populated if an acceptance criterion exists) |
| Lower Limit | Minimum acceptable (auto-populated) |
| Upper Limit | Maximum acceptable (auto-populated) |
The Pass/Fail status is calculated automatically: if the measured value is within the limits, ✔ (green) is shown; otherwise ✖ (red).
You can add multiple measurements for different elements on the same control sample.
In the edit form, below the results, click "Control Chart" and select an element.
The Levey-Jennings chart displays:
Use it to detect trends, biases or out-of-control points according to Westgard rules.
Type in the search field for quick text filtering.
Click the filter icon to open the filter panel:
| Filter | Type | Description |
|---|---|---|
| Status | Select | Filter by status (Pending, Pass, Fail) |
| Control Type | Select | Filter by category (Blank, Duplicate, CRM) |
| Lab Method | Select | Show samples for a single method only |
| Instrument | Select | Show samples for a single instrument only |
| Date From | Date | Range start date |
| Date To | Date | Range end date |
| Max Records | Number | Record limit for print/export (default: 200) |
Click the print icon. A PDF list is generated with:
From the row actions (⋮), select Preview or Download PDF to print an individual control sample with its results and chart.
Click the export icon to download a CSV file.
Printing and export respect active filters and the max records limit.
What is the difference between Blank, Duplicate and CRM?
How are limits auto-populated in measurements?
When selecting an element for a new measurement, the application looks up the corresponding acceptance criterion for the method–element combination and auto-fills the expected value, lower and upper limit fields.
How does auto-numbering work?
If you leave the "Document No." field blank during creation, the application assigns the next available code (format QC-YYYY-NNNN).
When should I change the status to Pass or Fail?
After logging all measurements, check the results (✔/✖) and update the status accordingly. The status does not change automatically — it is a deliberate decision by the analyst.
What should I do if a measurement is out of limits?
Per ISO 17025, you must document the non-conformity, investigate the causes and take corrective action. Record your findings in the "Notes" field and change the status to "Fail"