Testing
One technique used by employers is to set a test for applicants which encourages them to demonstrate their particular skills or knowledge in a manner that indicates their level of expertise.
The test can take the form of a scenario which is described in detail. Before the interview the candidate is given sufficient time to study the document and prepare themselves for questions based on the scenario. Many of the questions will be of the "What if " type where the candidate is asked to give their ideas of handling a particular situation or workplace problem. The scenario may involve technical details where the candidates technnical knowledge of actions and processes to be followed is tested.
The questioning line may be developed in an "ad hoc" manner depending on the answers given.