4.b Quality Assurance Flashcards
Random error to Proficiency Testing
Variation/Error present in all measurements, due to chance
RANDOM ERROR
improper calibration, deterioration of reagents, sample instability, changes in standard materials, instrument drift
Systematic Error
T/F?
T
mislabeling of sample, pipetting errors, improper mixing of sample and reagent, voltage fluctuations, temperature fluctuations
Random error
T/F?
T
most widely used quality control chart
Levey-Jennings Chart (Shewhart Plot)
dependent variable; vertical line; analyte concentration
Y-axis
independent variable; horizontal line; date or time
X-axis
What is the main cause of a trend in an analytical process?
A) Improper calibration of the instrument
B) Deterioration of reagents
C) Contamination of samples
D) Environmental changes
B
T/F
Trend is the gradual changes in the data
T
What is the main cause of a shift in an analytical process?
A) Improper calibration of the instrument
B) Deterioration of reagents
C) Variations in sample temperature
D) Inconsistent reagent mixing
A
T/F
Shift is the lagging change in data
F
Shift is the sudden/abrupt change in data
Control values that are far from the main set of values
OUTLIERS
systematic error
odd or even
even
random error
odd or even
odd
Westgard Multirule
One control value exceeds 2SD =
12s
One control value exceeds 3SD =
13s
The range of 2 consecutive control values are 4 SDs apart =
R4s
Four consecutive control values exceed 1SD =
41s
Two consecutive control values exceed 2SD =
22s
Ten consecutive control values are on the same side of the mean =
10x
Warning or Screening Rule for Rejection
12S
Westgard multirule for random error
12S, 13S, R4S
Westgard multirule for systematic error
22S, 41S, 10x
Comparison of previous results with the current result
DELTA CHECK
The next step in the connectivity process is TRANSMITTAL OF TEST RESULTS from the data manager to the LIS and/or hospital information system (HIS).
This is the INTERFACE PORTION of connectivity. (6th ed Bishop)
NOTE
