To use WCF as WCF Rest service you have to enable webHttpBindings. It support HTTP GET and POST verbs by [WebGet] and [WebInvoke] attributes respectively. To enable other HTTP verbs you have to do some configuration in IIS to accept request of that particular verb on .svc files.
Concurrent validity is a measure of how well a particular test correlates with a previously validated measure. It is commonly used in social science, psychology and education. Don't miss these related articles:
Construct validity is the approximate truth of the conclusion that your operationalization accurately reflects its construct. All of the other terms address this general issue in different ways. Second, I make a distinction between two broad types: translation validity and criterion-related validity. That's because I think these correspond to the two major ways you can assure/assess the validity of an operationalization.