What is content validity?

• A. The consistency of the measure over time
• B. The extent to which a measure represents all facets of a given concept
• C. The measure's ability to detect all true positives
• D. The degree to which a measure represents all facets of the construct

Answer: (D)

Content validity asks whether the test items cover all the important parts of the construct it’s meant to measure. If the instrument leaves out key aspects, it isn’t truly representing the domain, no matter how well the items perform on other metrics. The best choice says the measure’s degree of representation of all facets of the construct, which directly captures this idea: the items should span the entire domain they’re intended to assess.

It’s not about consistency of scores over time—that’s reliability. It’s also not about the test’s ability to detect true positives—that’s diagnostic sensitivity. The wording about representing all facets of the construct aligns with how content validity is defined in measurement.