Content Validity

The extent to which a test includes or represents all the content or domain of the construct that is being measured. In clinical psychology, a test developed to measure a psychological disorder, such as depression, needs to contain items that correspond to the symptoms involved in the disorder. The opinion of experts about the construct being measured may be one manner by which to determine content validity. Content validity requires more elaborate statistical procedures than face validity, which refers to whether a measure appears to measure that which it is intended to measure. A common method for establishing content validity consists of asking different judges or raters about whether the item is essential to measure the construct. The higher the degree of agreement among judges, the greater the level of content validity.