Setting Up the Experiment
Lab Settings Configuration
Before creating an LoQ experiment, complete the following one-time setup steps in Lab Settings:
- Add a lab area — A lab area must be created first. All analyzers and assays are organized under a location.
- Add an analyzer — Add at least one analyzer to the lab area representing the instrument used for the study.
- Add an analyte / assay — Click the analyzer row to open its detail page, then click Add assay. Select from the internal database or click Manual entry if the assay is not listed.
Creating the Experiment
When creating the LoQ experiment, you will configure the following required fields:
- Number of days — The number of test days. CLSI EP17-A2 requires a minimum of 3 days to capture between-day variability in precision.
- Runs per day — The number of analytical runs per day per reagent lot. Multiple runs per day contribute to within-laboratory precision estimates.
- Replicates per run — The number of replicate measurements per sample per run. CLSI EP17-A2 requires a minimum of 3 replicates per reagent lot / instrument / day combination.
- Number of reagent lots — CLSI EP17-A2 recommends a minimum of 2 reagent lots. The LoQ is calculated separately per lot and the maximum is reported.
- Concentration levels — The number of distinct concentration levels in the study. Nine levels spanning the low-end region are recommended for a well-constrained power model fit.
- Largest acceptable CV% — The maximum acceptable coefficient of variation — the precision acceptance threshold. The LoQ is the lowest concentration where the fitted CV% meets this threshold. This value should reflect the clinical precision requirements of the test and the analyte's medical decision context.
The following fields are optional but recommended for traceability:
- Operator — The person performing the measurements, retained in the report for documentation.
- Calibrator — The calibrator material or lot used during the study.
Entering Data
Data can be uploaded via the AI-assisted file import or entered manually through the spreadsheet-style entry table. The expected columns are:
| Column | Description |
|---|---|
| Sample ID | A unique identifier for each measurement row. Used to track individual observations in the dataset. |
| Lot | The reagent lot identifier (e.g., 1, 2). Measurements are grouped by lot for per-lot LoQ calculation. |
| Day | The test day number (e.g., 1, 2, 3). Used to assess between-day variability in precision. |
| Run | The run number within a day. Multiple runs per day contribute to within-laboratory precision. |
| Replicate | The replicate number within a run. Replicates within the same run assess repeatability. |
| Concentration Level | A label identifying the concentration level (e.g., "Level 1", "Pool 1"). Used to group measurements for CV% calculation per level. |
| Assigned Value | The known concentration for this level — from a reference material or prior assignment. Required for fitting the power model. |
| Result | The actual measured value from the instrument. Used with replicates at the same level to calculate measured CV%. |
Manual entry: When using the spreadsheet-style entry table, enter the Sample ID, Assigned Value, and Result for each measurement. Day, run, replicate, lot, and concentration level are structured by the form fields configured during experiment setup.