One of the most important input would be assessing competencies of the interviewer. Is he/she fit to ask the questions on the competencies in the interview?
There are various levels of the competencies. Level I is lowest and Level V is highest. Then interviewer can ask question only on those competencies for which his/her level is V. There should be third-party assessment of the competencies of the interviewers. Self-certification is not in the interest of the organisation.
From India, Bangalore