PHCH 667 : exam one Questions with Verified
Solutions
what is a reference range? range where values of 95% of the "healthy" individuals are
within (2 standard deviations)
coefficient of variation ratio of standard deviation to the mean
helps compare assays with different units
what is specificity and how is it calculated? true negative rate of the test
ability to correctly identify the "healthy"
TN/(FP + TN)
what is sensitivity and how is it calculated? true positive rate of the test
ability to correctly identify the "sick"
TP/(FN+TP)
what is positive predictive value? fraction of positive test results which are correct
,(how many were correctly identified as diseased)
how is PPV calculated? TP/(TP+FP)
what is negative predictive value? fraction of negative results correctly identified
(how many were correctly identified as healthy)
how is NPV calculated? TN/(TN+FN)
when is high sensitivity desired? the disease is serious and should not be missed
disease is treatable
(high ability to detect true positive)
when is high specificity desired? disease is serious but not treatable/curable - avoid
needless alarm
(high ability to detect true negative)
, what do clinical labs provide? objective and personalized patient information
hospital/clinical labs are driven by what? automation
high volume and cost efficiency
point-of-care testing is driven by what? miniaturization
convenience and cost
(immediate results and biosensor systems)
what are the classical analytical techniques? spectrophotometry
electrophoresis
electrochemistry
chromatography
mass spectrometry
what are the bio-molecular analytical techniques? enzymatic assays
immunoassays
Solutions
what is a reference range? range where values of 95% of the "healthy" individuals are
within (2 standard deviations)
coefficient of variation ratio of standard deviation to the mean
helps compare assays with different units
what is specificity and how is it calculated? true negative rate of the test
ability to correctly identify the "healthy"
TN/(FP + TN)
what is sensitivity and how is it calculated? true positive rate of the test
ability to correctly identify the "sick"
TP/(FN+TP)
what is positive predictive value? fraction of positive test results which are correct
,(how many were correctly identified as diseased)
how is PPV calculated? TP/(TP+FP)
what is negative predictive value? fraction of negative results correctly identified
(how many were correctly identified as healthy)
how is NPV calculated? TN/(TN+FN)
when is high sensitivity desired? the disease is serious and should not be missed
disease is treatable
(high ability to detect true positive)
when is high specificity desired? disease is serious but not treatable/curable - avoid
needless alarm
(high ability to detect true negative)
, what do clinical labs provide? objective and personalized patient information
hospital/clinical labs are driven by what? automation
high volume and cost efficiency
point-of-care testing is driven by what? miniaturization
convenience and cost
(immediate results and biosensor systems)
what are the classical analytical techniques? spectrophotometry
electrophoresis
electrochemistry
chromatography
mass spectrometry
what are the bio-molecular analytical techniques? enzymatic assays
immunoassays
