Parse- Intro to Lab Medicine

Question 1

what are reasons to order lab tests?

Answer 1

screen for a disease, diagnose a disease, follow progress of a disease and monitor therapy

Question 2

can you a assume an individual has cancer with high serum levels of CA-125?

Answer 2

no. both normal and cancer patients can have high CA-125 levels

Question 3

what is sensitivity equation?

Answer 3

(True Positives)/ (True positives+ False negatives)

Question 4

what is the specificity equation?

Answer 4

(True Negatives)/(True negatives+False positives)

Question 5

what is the equation for a predictive value (+test)?

Answer 5

(True positives)/ (True positives+ False positives)

Question 6

what is prevalence?

Answer 6

percent of people with disease in a given population at a point in time

Question 7

what happens as prevalence increases?

Answer 7

TP’s increase relative to FP’s, predictive value of a positive test increases, predictive value of a negative test decreases

Question 8

what is incidence?

Answer 8

number of new cases of disease in a population over time.