Quality Control/ Quality Assurance Flashcards
(41 cards)
- It is a system of ensuring accuracy and precision in the laboratory by including quality control reagents in every series of measurements
Quality Control
It is a process of ensuring that analytical results are correct by testing known sample in resemble patient sample
Quality Control
It is the ability of an analytical method to measure the smallest concentration of the analyte interest
Sensitivity
It is the ability of analytical method to measure only the analyte of interest
Specificity
It is the ability of an analytical method to maintain accuracy and precision over an extended period of time during which equipment
Realibility
It is an ability of an analytical method to detect the proportion of individual without the disease
Diagnostic specificity
It is an ability of an analytical method to detect the proportion of individual with the disease
Diagnostic sensitivity
Require high sensitivity so that no case is missed
Screening test
Require high specificity to be certain of the diagnosis
Confirmatory test
It involves the analyses control samples together with the patient specimen; detects both random and systematic error in a daily basis
Internal QC
It is important in maintaining long term accuracy of the analytical method
External QC
The gold standard for clinical elab external QC testing
College of American Pathologist
To ensure clinicians that patient results are accurate
Proficiency testing
Objectives of quality control
- To check the stability of the machine
- To check the quality of reagents
- To check technical operator errors
The accuracy of any assay depends on ____
Control solutions (QC materials)
General chemistry assay used ___ of control solutions
2 levels
Immuno assay used ___ of control solutions
3 levels
___ are calculated from mean and SD
Control limits
Ideal control limits is between ___
+/- 2 SD
Characteristics of an Ideal QC material
- Resembles human sample
-Inexpensive and stable for long period - No communicable disease
- with known analyte concentration
Present in all measurements; type of error that varies from sample to sample; Known as imprecision
Random Error
Error that influences observation consistently in one direction; known as inaccuracy
Systematic error
Pre analytical error
- incorrect patient identification
-improper patient preparation - mislabeled spicemen
- incorrect order of draw
Analytical Error (During)
- incorrect sample and reagent volume
- incorrect incubation of solutions and timing
- equipment malfunction
