QUALITY ASSURANCE and QUALITY CONTROL Flashcards
Process by which lab ensures quality results by closely monitoring preanalytical, analytical, & post analytical stages of testing
QUALITY ASSURANCE
Examples of Preanalytical phase; everything that precedes test performance:
- Test ordering
- Patient preparation
- Patient ID
- Specimen collection
- Specimen transport
- Specimen processing
Examples of Analytical phase; everything related to assay:
- Test analysis
- Quality control (QC)
- Reagents
- Calibration
- Preventive maintenance (involves machines)
Examples of Postanalytical phase; everything that comes after test analysis:
- Verification of calculations & preference ranges
- Review of results
- Notification of critical values
- Result reporting
- Test interpretation by physician
- Follow-up patient care
Part of analytical phase of quality assurance; process of monitoring results from control samples to verify accuracy of patient results
Quality Control (QC)
It is the average of data points:
Mean
It is the midpoint of distribution
Median
It is the most frequent observation
Mode
It is the difference between highest and lowest value; easiest measure of spread
Range
Most frequently used measure if variation:
Standard Deviation (SD)
An index of precision used to compare the dispersion of two or more groups of data with different units/concentrations
Coefficient of variation (CV)
Used to determine if there is a significant difference between the means of two groups of data; compares accuracy
T-test
mnemonic: “ATM”
A - Accuracy
T - T-test
M - Mean
Used to determine if there is a significant difference between the SD of two groups of data; compares precision:
F-test
mnemonic: “SPF”
S - SD
P - Precision
F - F-test
____% of the data fall between +/- SD from the mean
68%
_____% of the data fall between +/-2 SDs from the mean.
95%
_____% of the data fall between +/-3 SDs from the mean
99%
