3. Method evaluation Flashcards
A determination of the analytical and clinical performance characteristics of a test.
method evaluation
an AMR must be verified every…
6 months
don’t need to be AMR verified
analytes with multipoint calibrations
The lowest concentration that can be distinguished from background noise
Limit of Blank (LoB)
The lowest number that will almost always have a non-zero result
Limit of Detection (LoD)
The lowest concentration that can be quantified reliably
Limit of Quantification (LoQ)
how to select specimens for a precision study
Select specimens near at least 2 control levels that represent medically important decision limits
Indicates the extent of linear relationship between the methods
correlation coefficient “r”
r is influenced by…
random errors only
——- cannot be based on r
method accuracy
axes for method comparision studies
X - results of reference method
Y - results of new method
most common interfering substances
Lipids (Lipemia)
Hemoglobin (Hemolysis)
Bilirubin (Icterus)
describe interference study
The interfering substance is “spiked” into a known sample (no analyte added)
Added volume < 10%
Run in duplicates
nonpreferred way to get a reference interval
may be necessary for…
take data from the Electronic Medical Records System (EMR) to establish the reference interval
pediatrics
