Sensitivity, specificity and predictive value
Not what you're looking for?
Please see the attachment.
12. Table 1. Results of a screening test for diabetes, using a cutoff point of 160 mg.dl.
True Diagnosis
Test result Diabetic Not Diabetic Total
Positive 34 20 54
Negative 116 9,830 9,946
Total 150 9,850 10,000
The specificity of the screening test for diabetes is
a. 0.3%
b. 22.6%
c. 63.0%
d. 77.4%
e. 99.7%
Save Answer
13. The sensitivity of the screening test for diabetes is
a. 0.3%
b. 22.6%
c. 63.0%
d. 77.4%
e. 99.7%
Save Answer
14. The positive predictive value of the screening test for diabetes is
a. 0.3%
b. 22.6%
c. 63.0%
d. 77.4%
e. 99.7%
Save Answer
15. If the cutoff is set higher than 180 mg/dl, how would this affect the sensitivity and specificity?
a. no changes
b. sensitivity increase, specificity decrease
c. sensitivity decrease, specificity increase
d. both decrease
e. both increase
Save Answer
16. What will be the effect on false negatives (FN) and false positives (FP) of setting the cutoff higher than 180 mg/dl?
a. FP increase, FN unchanged
b. no changes
c. FP increase, FN decrease
d. FP decrease, FN increase
e. both decrease
Save Answer
17. When the screening cutoff point was lowered to a blood glucose value of 130 mg/dl, 164 persons now tested positive; 98 of these people were among the 9,850 persons judged by diagnostic tests not to have diabetes. Compute the sensitivity, specificity and predictive value of a positive test at this cutoff level in the next 3 questions Sensitivity is
a. 1%
b. 40%
c. 44%
d. 56%
e. 60%
f. 99%
Save Answer
18. Specificity is
a. 1%
b. 40%
c. 44%
d. 56%
e. 60%
f. 99%
Save Answer
19. Positive predictive value is
a. 1%
b. 40%
c. 44%
d. 56%
e. 60%
f. 99%
Purchase this Solution
Solution Summary
The solution calculates sensitivity, specificity and predictive value
Solution Preview
Please see the attachment.
12. (Points: 2)
Table 1. Results of a screening test for diabetes, using a cutoff point of 160 mg.dl.
True Diagnosis
Test result Diabetic Not Diabetic Total
Positive 34 20 54
Negative 116 9,830 9,946
Total 150 9,850 10,000
Condition is
Present Absent Total=
Test is Positive True Positive=34 False Positive=20 54
Negative False Negative=116 True Negative=9830 9946
Total= 150 9850 10000
The specificity of the screening test for diabetes is
a. 0.3%
b. 22.6%
c. 63.0%
d. 77.4%
e. 99.7%
Answer: e. 99.7%
Specificity = True Negatives/ (False Positive + True Negative)
= 9830 / (20 + 9830) = 99.7 %
13. (Points: 2)
The sensitivity of the screening test for diabetes is
a. 0.3%
b. 22.6%
c. 63.0%
d. 77.4%
e. 99.7%
Answer: b. 22.6%
Sensitivity = True Positives / (True Positives + False Negatives)
= 34 / (34 +116) = 34 /150 = 22.6 %
14. (Points: 2)
The positive ...
Purchase this Solution
Free BrainMass Quizzes
Know Your Statistical Concepts
Each question is a choice-summary multiple choice question that presents you with a statistical concept and then 4 numbered statements. You must decide which (if any) of the numbered statements is/are true as they relate to the statistical concept.
Measures of Central Tendency
This quiz evaluates the students understanding of the measures of central tendency seen in statistics. This quiz is specifically designed to incorporate the measures of central tendency as they relate to psychological research.
Measures of Central Tendency
Tests knowledge of the three main measures of central tendency, including some simple calculation questions.
Terms and Definitions for Statistics
This quiz covers basic terms and definitions of statistics.