Clinical Chemistry 3 Flashcards
What is the purpose of analytical methods
to measure biological analytes in pathology specimens
results help in diagnosis, screening, prognosis and monitoring treatment
Analytical method
a set of instructions which describe the procedure, materials and equipment necessary to obtain a result
Calibration
the process of relating the value indicated on the scale of an instrument or analytical device to the quantity required to be measured
Standard
a material or solution with which the sample is compared in order to determine a result
Blank
this is treated exactly as a sample or standard but does not contain the analyte to be measured and used to zero instruments
Control
a material or solution which contains a known quantity of the analyte of interest and is used for quality control purposes
What should analytical methods have
reliability
practicality
What are test results subject to
analytical variation
biological variation
Accuracy
this is the ability of a method to give results which are close to the true value of the substance being measured
Precision
this is the ability of a method to provide the same value every time the method is used to measure a particular analyte in the same specimen
Sensitivity
this is the ability of a method to detect small amounts of the analyte
LimitofDetection
the smallest amount of the analyte that can be distinguished from the blank
Specificity:
this is the ability of a method to detect only the test substance
What is biological variation affected by
sex
age
diet
time of day posture
stress
exercise
menstrual cycle drugs
What are methods assessed for
speed
cost
skillrequirements dependability
safety
