Measurement Uncertainty (MU) Record
Required by: ISO 15189:2022 Cl. 7.3.4 — Measurement uncertainty of measured quantity values
A stated, periodically reviewed estimate of the uncertainty attached to each quantitative result.
Checked against NABL 112A (Issue 01, 18-Dec-2024) · page updated 23 September 2026
How often it must be recorded
Established per quantitative analyte and reviewed annually where possible.
Every field this record must carry
An assessor reads the record, not the intention behind it. A field left off the form is a finding, however well the work was actually done.
- Analyte and measuring system
- IQC data period used
- Routine imprecision (%CV)
- Bias component and its source
- Combined and expanded uncertainty
- Coverage factor stated
- Date calculated and next review
- For qualitative tests: the listed factors contributing to uncertainty
What NABL 112A actually says
NABL 112A recommends a minimum of six months of IQC data to calculate routine imprecision, updated annually where possible. For qualitative tests the laboratory shall enlist the factors which could contribute to uncertainty and show they were given due attention.
Source: NABL 112A — Specific Criteria for Accreditation of Medical Laboratories, Issue 01, 18-Dec-2024, 108pp. Downloaded from nabl-india.org 2026-09-23. Paraphrased with attribution. ISO 15189:2022 clause numbers and titles are cited as references; the standard's text is copyrighted and is not reproduced here.
What an assessor actually asks for
Reasoning from the clause, not from a published checklist — NABL does not publish assessor scripts. Treat this as how the requirement is normally evidenced.
- The record itself, for a period they choose — not a blank template.
- Completeness across the period. Gaps are the finding; a perfect January and an empty March reads worse than a consistently modest record.
- Who recorded and who verified, with dates. An unsigned record is not evidence that the work was checked.
- The linked procedure — the SOP that says this record must exist, at this frequency, in this format.
- What happened when it went wrong. Every record above has a failure path, and the action taken is usually the part that is missing.
Records this one depends on
Where the software fits
HealthFlow is lab software, not an accreditation body. It is not NABL accredited and using it does not make a laboratory accredited or compliant — the records above are the laboratory's own responsibility.
What it does do is produce some of this evidence as a by-product of normal work: turnaround time is measured per test on the owner dashboard, reports are versioned and locked on authorisation with dual signatures, every report access is written to an append-only audit trail enforced at the database, retained two years, and all of it exports at any time.