The theory behind content validity, as opposed to face validity, is that experts are aware of nuances in the construct that may be rare or elusive of which the layperson may not be aware. For example, if you submitted your attitude survey to Kurt Goldstein for a content validity check, he may say you need to have something to assess whether your respondents can break something down into component parts, then resynthesize it, as this is an important aspect of attitude, and otherwise you have no content validity. For an example of a study where a content validity check was used for an attitude assessment, click here . Another example measures influences , and another measures impacts . Many studies procede following content validity acvhievement, however this does not necessarily mean the measures used are entirely valid.
Criterion validity is a more rigorous test than face or content validity.
Criterion validity means your attitude assessment can predict or agree with constructs external to attitude. If you administer your attutude survey to someone who is cheerful and smiling a lot, but they rate low, indicating a negative attitude, your survey may not have concurrent validity. For an extremely thorough example of research on the use of solution-focused group therapy with school children, which includes a concurrent validity check, click here . Finally, the most rigorous validity test you can put your attitude survey through is the construct validity check. These other constructs do not necessarily have to be predictive or concurrent, however often times they are.