Quality Assurance Flashcards
Define Sensitivity
a measure of frequency of the test being positive in animals that have the disease
(how many truely afflicted animals will be missed by a test)
How do you calculate sensitivity
TP / (TP+FN) x 100
Define Specificty
A measure of the frequency of the test being negative (or normal) in animals that do not have the disease
How do you calculate specificity
TN / (TN + FP) x 100
If you have a test with high sensitivity and you get a negative result, it increases your confidence that the patient (does/does not) have the disease in question
does not
If a test has a low sensitivity, you (can/cannot) rule out the disease based on a negative result
cannot
If a test has a high specificity and you get a positive result, it increases your confidence that the patient (has/does not have) the disease in question
Has
If a test has a low specificity, you (can/cannot) conclude a positive result indicates the disease in question
cannot
positive predictive value (PPV)
tells you what % of animals with a positive (abnormal) test result actually have the disease
how do you calculate PPV
TP / (TP+FP) x100
Negative predictive value (NPV)
tells you what percent of animals with a negative (normal) test don’t have the disease
What are the phases of sample analysis?
Pre-analytical, analityical, Post-analytical
define quality assurance
the planned procedures that are implemented to monitor, identify and improve laboratory performance in order to minimize all types of lab errors
goal for QA programs
detect and prevent errors in all phases of lab testing
define quality control
the procedures we apply to monitor analytic performance of the instrument and use to detect and minimize analytical errors
define accuracy
how close is the result to the true value
define precision
how repeatable is the result
