Refer to the table which summarizes the results of testing for a certain disease. $$\begin{array} { l | c c }
& \text { Positive Test Result } & \text { Negative Test Result } \
\hline \text { Subject has the disease } & 119 & 6 \
\text { Subject does not have the disease } & 13 & 177
\end{array}$$
If one of the results is randomly selected, what is the probability that it is a false negative (test indicates the person does not have the disease when in fact they do)? What does this probability suggest about the accuracy of the test?
A) 0.0413; The probability of this error is low so the test is fairly accurate.
B) 0.581; The probability of this error is high so the test is not very accurate.
C) 0.0190; The probability of this error is low so the test is fairly accurate.
D) 0.0480; The probability of this error is low so the test is fairly accurate.

Question

Refer to the table which summarizes the results of testing for a certain disease. $$\begin{array} { l | c c } 
& \text { Positive Test Result } & \text { Negative Test Result } \
\hline \text { Subject has the disease } & 119 & 6 \
\text { Subject does not have the disease } & 13 & 177
\end{array}$$ 
If one of the results is randomly selected, what is the probability that it is a false negative (test indicates the person does not have the disease when in fact they do)? What does this probability suggest about the accuracy of the test?
A) 0.0413; The probability of this error is low so the test is fairly accurate.
B) 0.581; The probability of this error is high so the test is not very accurate.
C) 0.0190; The probability of this error is low so the test is fairly accurate.
D) 0.0480; The probability of this error is low so the test is fairly accurate.

Quizplus · Accepted Answer

The probability of a false negative is calculated as the number of false negatives (6) divided by the total number of tests (315). This gives 6/315 = 0.0190, indicating a low probability of this error, suggesting the test is fairly accurate.

Refer to the Table Which Summarizes the Results of Testing