Unit 8- QA Flashcards
(25 cards)
What is True Positive
both the test and gold standard were positive for disease
What is True Negative
both the test and gold standard were negative for disease
What is False Positive
the test was positive for disease, but the gold standard showed no disease
What is False Negative
the test was negative for disease, but the gold standard was positive for disease
Define Sensitivity
ability of a test to detect a positive result
Define Specificity
ability of a test to detect the absence of disease and give a negative diagnosis
Define negative predictive value
measures how often the test is correct when negative for disease
Define positive predictive value
measures how often the test is correct when positive for disease
Define overall accuracy
measures the percentage of examinations that agree with the gold standard
What section of the chi square does the true positive number go in?
Top Left
What section of the chi square does the true negative number go in?
Bottom Right
What section of the chi square does the false positive number go in?
Top Right
What section of the chi square does the false negative number go in?
Bottom Left
What part of the chi square determines sensitivity?
The left column
What part of the chi square determines specificity?
The right column
What part of the chi square determines positive predictive value?
The top row
What part of the chi square determines negative predictive value?
The bottom row
What is the Chi Square equation?
true value / (total)
What is the equation for overall accuracy?
True positive + True negative / cumulative total values
Define quality assurance. Who is in charge of this?
QA is a legal and medical necessity. The sonographer is responsible for QA.
What are the requirements of QA
assessment, repairs, maintenance, record keeping
What are the goals of QA
proper operation of equipment, detect changes, minimize downtime, reduce non-diagnostic and repeat exams.
What are methods of QA
test under known conditions, use constant settings, use measurable phantom, use an identical environment
What are objective standards?
factual, unbiased, repeatable, measurable
