Content validity ensures that he measure includes an adequate and representative set of items that tap the concept. The more the scale items represent the domain or universe of the concept being measured, the greater the content validity. To put it differently content validity is a function of how well the dimensions and elements of a concept have been delineated. A panel of judges can attest to the content validity of the instrument. Kidder and Judd cite the example where a test designed to measure degrees of speech impairment can be considered as having validity if it is so evaluated by speech impairment can be considered as having validity if it is so evaluated by a group of expert judges.
Face validity is considered by some as a basic and a very minimum index of content validity. Face validity indicates that the items that are intended to measure a concept do on the face of it look like they measure the concept. Some researchers do not see it fit to treat face validity as a valid component of content validity. Criterion related validity is established when the measure differentiates individuals on a criterion it is expected to predict. Concurrent validity is established when the scale discriminates individuals who are know to be different.
Face validity is considered by some as a basic and a very minimum index of content validity. Face validity indicates that the items that are intended to measure a concept do on the face of it look like they measure the concept. Some researchers do not see it fit to treat face validity as a valid component of content validity. Criterion related validity is established when the measure differentiates individuals on a criterion it is expected to predict. Concurrent validity is established when the scale discriminates individuals who are know to be different.
