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:
A reliable instrument produces consistent results regardless of the setting, yet reliability does not ensure accuracy or validity. Validity refers to an instrumentâs capacity to accurately measure what the researcher intended to measure. Reliability must be accompanied with validity regarding an instrument worthy of use in conducting doctoral research. A few simple examples help explain the meaning of reliability and validity.