Consultant John Shenton explains how to make competency-based interviews work for your organisation and why they are useful.
Competence based interviews are now very popular. As with all "test" based interviews, you need something to measure against. To be able to carry out a competence based interview, you need to create competence models for the job role. Once you have these you need a way to measure the interviewee's strengths and weaknesses against such models and then you can be very specific in your questioning.
The reason this is now so popluar is that it is very difficult for an interviewee to fudge their answers and it makes it much easier for the interviwer to probe for logic and proof of understanding.
To be more specific:
1) The relevance of a competence and the related competencies in the IT field, for example, will be split into two parts: hard and soft. For the hard competence, relevance will be about specific knowledge relating to "up to date" systems. The softer side will be related to the person's desire to undertake further training if available. Cultural-based issues will also come under the soft competence model and I believe you would be looking to measure what a person knows how to do today in this particular role.
2) Non work-based examples - Many competence models include things that we all use every day. As you rightly point out, communication in all areas is the most obvious. So if a person is a good presenter in a non work environment, why shouldn't this be representative in a work environment. The competence is described as being able to do something to an aceptable level in that job role. This still does not cover a person's willingness to do anything and the competence must, therefore, describe the action that is acceptable to your organisation.
3. Academic examples might give you a reason to question an interviwee about how and why they undertook this task. Relating an example to the job requirement once again requires that the interviewer knows what the job requires and what level of emphasis a candidate is likely to put on this competence if they were offered the job.
To deal with these grey areas, competence models for the primary competencies required of the job holder, measure these specifically, and question the results.