Clinically reportable range: range of analyte values that are reported as a quantitative result, allowing for specimen dilution or other pretreatment used to extend the actual AMR. Reportable range: span of test result values over which the lab can establish or verify the accuracy of the measurement response.
What is AMR range?
The ANALYTICAL MEASUREMENT RANGE (AMR) is the range of analyte values that a method can directly measure on the specimen without any dilution, concentration, or other pretreatment not part of the usual assay process.
What is the difference between AMR and reportable range?
Reportable range is the functional range of an assay over which the concentrations of an analyte can be measured with acceptable accuracy and precision. AMR is defined as the range of values an instrument can report directly without dilution or concentration.
What is AMR verification?
AMR validation is a process used to verify the linear relationship between the analytical results of a method and the concentration of analyte over the entire measurement range.
How do I validate AMR?
The key steps in AMR validation are: 1) obtaining suitable test material (patient samples, commercial proficiency testing or linearity survey material, or calibrators from a different lot than the one used to calibrate the assay); 2) testing at least three concentrations close to the low end, high end, and midpoint of …
What is calibration verification?
Calibration verification means the assaying of materials of known concentration in the same manner as patient samples to substantiate the instrument or test system’s calibration throughout the reportable range for patient test results.
What is the upper range limit of an assay?
The upper limit of quantification is the highest concentration in the calibration curve which can be determined with a given analytical assay with the required precision and accuracy. In most cases the precision and accuracy must be ±15% at the high end of the calibration curve.
How do you find the linearity range?
Linearity should be confirmed for the expected working range, including the chosen matrix. A linear range can be found from the linearity assessment experiments, however, the criteria for a linear range can be different. A linear range should cover 0–150% or 50–150% of the expected analyte concentration.
How do you perform calibration?
Although the exact procedure may vary from product to product, the calibration process generally involves using the instrument to test samples of one or more known values called “calibrators.” The results are used to establish a relationship between the measurement technique used by the instrument and the known values.
Why is calibration needed?
The primary significance of calibration is that it maintains accuracy, standardization and repeatability in measurements, assuring reliable benchmarks and results. Without regular calibration, equipment can fall out of spec, provide inaccurate measurements and threaten quality, safety and equipment longevity.
What is a good limit of detection?
A signal-to-noise ratio between 3 or 2:1 is generally considered acceptable for estimating the detection limit. The quantification limit of an individual analytical procedure is the lowest amount of analyte in a sample which can be quantitatively determined with suitable precision and accuracy.
How do you find the detection limit?
The detection limit is estimated from the mean of the blank, the standard deviation of the blank, the slope (analytical sensitivity) of the calibration plot and a defined confidence factor (e.g. 3.2 being the most accepted value for this arbitrary value).
What is reportable range?
Reportable range is the functional range of an assay over which the concentrations of an analyte can be measured with acceptable accuracy and precision. Reportable range should not be confused with reference range.
Do the CLIA requirements for calibration have changed?
No, the CLIA requirements for calibration have not changed. The laboratory is responsible for performing calibration as directed by the manufacturer’s test system instructions, and when calibration verification of the test system (see below) does not produce acceptable results.
What is the reportable range of the analyte?
A reportable range will be established for each analyte tested. The upper limit of the reportable range will be set at the concentration of the highest standard tested which exhibited acceptable results for linearity, accuracy and precision.
What is the reportable range of Amr and CRR?
Reportable Range. CRR is typically wider than AMR. Values greater than or less than the CRR are reported as greater than (>) or less than (<). CRR is a clinical decision made by the medical director and does not require periodic revalidation. Dilution or concentration protocols must be documented for each analyte.
