PHCH 667 Questions with 100% Solutions
What's in the Buffy Coat? - ✅✅ White blood cells and platelets
What is hematocrit? - ✅✅ RBC/ total volume, packed cell volume (PCV)
What is MCV? - ✅✅ Mean cell volume: average volume of RBC
What does elevated or decreased MCV levels indicate? - ✅✅ Elevated: enlarged
erythrocytes, B12 and folic acid deficiency
Decreased: small erythrocytes, iron deficiency
What is the role of platelets? - ✅✅ Blood clot formation
Why are statistics used in clinical chemistry? - ✅✅ Statistics are used to draw
"lines in the sand" for patient specimens, control specimens and analytical test
calibrators.
To evaluate clinical lab result, know if result is within normal range, determine if
test result is valid, determine if assay is behaving weird or abnormal.
How does accuracy compare with precision? - ✅✅ Accuracy: degree of
correlation of results between assay being investigated and the true value (Mean)
Precision: degree of variability of assay results when known specimens are tested
repeatedly in one run or over several days (Standard deviation)
, How to calculate mean and standard deviation? How is it related to accuracy and
precision of an analytical method? - ✅✅ Mean is arithmetic average of data
point values around mean and gives precision (square root of variance)
Mean: add all data points and divide by the number of points collected. SD: find
the mean, for each data point subtract the mean and square the result, find the mean
of the squared differences. Take squared root of that.
Accuracy: mean, precision: SD
What is 68-95-99.7% rule? - ✅✅ Gaussian distributions represent normal
distribution of data.
The rule state that normal/reference range of healthy individuals fall within 95% or
2 SD (1 SD is 68%, 3 SD is 99.7%)
What is the most commonly used "acceptable level of significance" used in clinical
chemistry? - ✅✅ 95%
What is a reference range? - ✅✅ Normal or reference range is typically range
where values of 95% of the "healthy" individuals are within, anything outside is
abnormal and is considered a critical value
What is specificity and how is it calculated? - ✅✅ Specificity: proportion of
HEALTHY subjects correctly classified/ ability to exclude a diagnosis, detect a
true negative, in a healthy person
Specificity= TN/(FP+TN)
What's in the Buffy Coat? - ✅✅ White blood cells and platelets
What is hematocrit? - ✅✅ RBC/ total volume, packed cell volume (PCV)
What is MCV? - ✅✅ Mean cell volume: average volume of RBC
What does elevated or decreased MCV levels indicate? - ✅✅ Elevated: enlarged
erythrocytes, B12 and folic acid deficiency
Decreased: small erythrocytes, iron deficiency
What is the role of platelets? - ✅✅ Blood clot formation
Why are statistics used in clinical chemistry? - ✅✅ Statistics are used to draw
"lines in the sand" for patient specimens, control specimens and analytical test
calibrators.
To evaluate clinical lab result, know if result is within normal range, determine if
test result is valid, determine if assay is behaving weird or abnormal.
How does accuracy compare with precision? - ✅✅ Accuracy: degree of
correlation of results between assay being investigated and the true value (Mean)
Precision: degree of variability of assay results when known specimens are tested
repeatedly in one run or over several days (Standard deviation)
, How to calculate mean and standard deviation? How is it related to accuracy and
precision of an analytical method? - ✅✅ Mean is arithmetic average of data
point values around mean and gives precision (square root of variance)
Mean: add all data points and divide by the number of points collected. SD: find
the mean, for each data point subtract the mean and square the result, find the mean
of the squared differences. Take squared root of that.
Accuracy: mean, precision: SD
What is 68-95-99.7% rule? - ✅✅ Gaussian distributions represent normal
distribution of data.
The rule state that normal/reference range of healthy individuals fall within 95% or
2 SD (1 SD is 68%, 3 SD is 99.7%)
What is the most commonly used "acceptable level of significance" used in clinical
chemistry? - ✅✅ 95%
What is a reference range? - ✅✅ Normal or reference range is typically range
where values of 95% of the "healthy" individuals are within, anything outside is
abnormal and is considered a critical value
What is specificity and how is it calculated? - ✅✅ Specificity: proportion of
HEALTHY subjects correctly classified/ ability to exclude a diagnosis, detect a
true negative, in a healthy person
Specificity= TN/(FP+TN)
