Module 2 Flashcards
Non-targeted analytes which may impact the ability to detect, identify, or quantitate a targeted analyte:
Interferences
The lowest concentration of an analyte in a sample that can be reliably measured with acceptable bias and precision:
Limit of Quantitation
Day 1 mean: 23 ng/mL
Day 2 mean: 17 ng/mL
Day 3 mean: 21 ng/mL
Day 4 mean: 22 ng/mL
Day 5 mean: 19 ng/mL
Nominal Concentration: 15 ng/mL
What is the Bias(%)?
36%
The coefficient of variation of an analytical method is determined by performing a defined number of replicate assays and then making the following calculation:
Standard deviation divided by the mean and expressed as a percentage
The precision and accuracy in measurement of an analyte under a variety of analytical conditions (e.g., storage conditions):
Robustness
The ability to detect an analyte among a similar class of related compounds or their metabolites:
Method Specificity
This standard and its progeny rely on a “scientific knowledge” approach to determining whether expert testimony is not only relevant, but also reliable, and, therefore, admissible as evidence:
Daubert Standard
Random error plus systematic error equals:
Total Error
The range of analyte where results are proportional to the true concentration of analyte in the sample without modification defines:
Analytical Measure Range
The contamination of a sample(s) or extract(s) caused by a previously run sample or extract:
Carryover
The acronym ISO stands for:
International Organization for Standardization
These studies are conducted to ensure that results reflect the true analyte concentration in a sample:
Accuracy
These studies are conducted to determine the reproducibility of measurements:
Imprecision
Accuracy of a result is based upon these two variables:
Bias and Precision
Defined as the absolute recovery of analyte without use of an internal standard:
Analytical Recovery
This is an indicator of the linearity of a calibration line:
Correlation coefficient
What are the Federal Urine Drug testing screening cut-offs?
6MAM = 10 ng/mL
Cocaine metabolites = 150ng/mL
PCP = 25 ng/mL
Opiate metabolites = 3000 ng/mL
Amphetamines = 500 ng/mL
Marijuana metabolites = 50 ng/mL
What anticoagulant is in a purple top tube?
EDTA
What can trigger a positive amphetamine result on immunoassay?
Beta-pheneylamine
What is the normal pH range for urine?
4.5 - 9
What is a normal concentration for creatinine?
> 20 mg/dl
What is a normal specific gravity?
1.0020 - 1.0200
What does SAMHSA stand for?
Substance Abuse and Mental Health Services Administration
What describes how close the estimate is to the actual value?
Accuracy
What describes the variance of the estimates?
Precision
An error in measurement by factors which vary from one measurement to another?
Random Error
