Exam 4 Question 96

[Karen C]

Question 96 states:
You notice many questions referring to women’s health topics on your NCS examination. This is not only frustrating because you have not studied this content but also shows that the NCS has poor:
 a. Internal validity
 b. External validity
 c. Content validity
 d. Construct validity

the Answer is C, but if there are questions about women’s health topics doesn’t that affect the Construct validity of the test?

[Chrissy Durrough Lugge]

Hi Karen,

Construct and content validity are closely related but distinct concepts. Construct validity refers to how well a test measures the abstract concept it is supposed to measure. In this case, does the exam accurately measure whether someone is a neurologic specialist or is it testing some other construct?

Content validity refers to how representative a test is to all aspects of the construct. For example, does the NCS exam assess all domains of neurologic practice? If relevant aspects are omitted or irrelevant topics are included, content validity is threatened.

Another way to think about it is that construct validity relates to the test as a whole while content validity relates to the questions. A test with low content validity or criterion-related validity likely also has low construct validity. For this question, we can’t actually say whether the overall test accurately determines whether someone is an expert in neurologic practice (maybe these women’s health questions actually improve the algorithm?), so we can’t judge the construct validity. We can say that the women’s health questions are irrelevant to neurologic practice and that threatens content validity.

For further clarification, here is a nice article that summarizes the types of validity: https://www.scribbr.com/methodology/types-of-validity/

Hope this helps!

Chrissy

[Author]

Posts