Lead Author(s): Jeff Martin, MD

Types of Validity

There are two types of validity:

Measures of Validity

Validity is measured in terms of sensitivity (ability to measure who HAS the characteristic: disease or exposure) and specificity (ability to measure who DOES NOT HAVE the characteristic: disease or exposure).

Importance of Validity

In terms of study validity, though, the key question is not when is the study being carried out, but: