Author Question: A likelihood ratio above 1 indicates that a diagnostic test showing a: A. Positive result is ... (Read 71 times)

jwb375 · **on:** Jun 25, 2018

A likelihood ratio above 1 indicates that a diagnostic test showing a:

A. Positive result is strongly associated with the disease
B. Negative result is strongly associated with absence of the disease
C. Positive result is weakly associated with the disease
D. Negative result is weakly associated with absence of the disease

Question 2

If a diagnostic study has high specificity, this indicates a:

A. Low percentage of healthy individuals will show a normal result
B. High percentage of healthy individuals will show a normal result
C. High percentage of individuals with a disorder will show a normal result
D. Low percentage of individuals with a disorder will show an abnormal result

mohan · **Reply #1 on:** Jun 25, 2018

Answer to Question 1

ANS: A
The likelihood ratio is the probability that a positive test result will be associated with a person who has the target condition and a negative result will be associated with a healthy person. A likelihood ratio above 1 indicates that a positive result is associated with the disease; a likelihood ratio less than 1 indicates that a negative result is associated with an absence of the disease.

Answer to Question 2

ANS: B
The specificity of a diagnostic study is the percentage of normal, healthy individuals who have a normal result. The greater the specificity, the greater the percentage of individuals who will have negative, or normal, results if they do not have the target condition.