QA: Gold Standard

the main purpose of quality assurance is…

• to assess how accurate is the diagnostic exam

• allow for ultrasound results to be compared to a “gold standard” test

what are examples of Gold Standard tests?

• digitals subtraction angiography

• computed tomogrpahy angiography with contrast (CTA)

• magnetic resonance angiography (MRA)

• surgical findings

• clinical outcome

what are the methods to assess efficacy?

sensitivity and specificity

how good is a test for detecting disease or how good is the test for ruling out disease?

the ability of a test to find a disease when it is present, is called?

sensitivity

the ability of a test to show there is no disease when there is no disease present, is called?

specificity

methods to assess reliability are?

• true positive

• false positives

• positive predictive value

• true negative

• false negative

• negative predictive values

portion of individuals with a positive test result that truly have the condition or disease is called?

PPV (positive predictive value)

portion of individuals with a negative test result that truly do not have the condition or disease, is called?

negative predictive value (NPV)

• the portion of all individuals whose test results align with their condition.

• the percentage of time the ultrasound results was correct

this indicates?

accuracy

the portion or percentage of patients in the entire group, being assessed, to have the disease or condition

prevalence

label the red and orange

test and Gold standard

how to calculate for sensitivity?

sensitivity = TP/ (TP + FN)

ability of a test to find a disease when it is present

How to calculate for specificity?

Specificity = TN / (FP +TN)

ability of a test to show there is no disease when there is no disease present

how to calculate for PPV?

PPV = TP / (TP + FP)

how to calculate for NPV?

NPV = TN / (FN + TN)

how to calculate for accuracy?

accuracy = TP + TN / (TP + FN + FP+ TN)

how to calculate for prevalence?

prevalence = TP + FN (TP + FN + FP + TN)