Setting total allowable error (TEa) for an analyte
Record an analyte’s total allowable error as an absolute value, a percentage, the greater of both, or different limits above and below a concentration.
Total allowable error (TEa) is the amount of error your lab accepts in a single result. Each analyte in the test directory carries one TEa, which validation studies and quality control use as their performance goal.
Where it comes from
When you add an analyte from the platform catalog, its default TEa and the source of that limit are copied onto your analyte. You can change it at any time, and you enter it yourself for an analyte added by hand.
Setting it
Click the "Allowable Error" field ("Click to configure") to open "Configure Total Allowable Error (TEa)", then answer two questions:
- Is it the same at every concentration? Choose one limit for all concentrations, or a limit that differs above and below a threshold.
- What kind of limit is it? Choose an absolute value in the analyte's units, a percentage, or the greater of an absolute value and a percentage.
The result is written in a standard form:
| Kind | Example |
|---|---|
| Absolute | ±2.0 |
| Percentage | ±10% |
| Greater of the two | ±6 or ±8% (whichever is greater) |
| Different above and below a threshold | ±2 if ≤ 20 or ±10% if > 20 |
Record where the limit comes from in the "Source" and "Link" fields, for example CLIA proficiency testing criteria or biological variation data, so a reviewer can see why it was chosen.
Where it is used
In validation studies, precision, method comparison, linearity and other modules compare their results with the TEa, or with the share of it allocated to imprecision or bias, unless a study sets its own limit. In quality control, the TEa feeds the Sigma estimate behind the suggested Westgard rules.