The prevalence of undetected diabetes in a population to be screened is approximately 1.5% and it is assumed that 10,000 persons will be screened. The screening test will measure blood serum sugar content. A value of 180 mg percent or higher is considered positive. The sensitivity and the specificity associated with this screening are 22.9% and 99.8% respectively.
a. Set up a fourfold table with the appropriate numbers in each cell of the table. (3 pts. per box)
+ - Total
Prevalence = 1.5%
Population = 10,000
Sensitivity = 22.9%
Specificity = 99.8%
Calculate the following values: (3 points each)
b. The percentage of false positive error rate.
c. The percentage of false negative error rate.
d. The predictive value of a positive test.
e. The predictive value of a negative test.
f. Based on the calculations above, how many false positives and negatives will occur if 100,000 people are screened?