Assessment Interviews are less structured, more conversational approaches to exploring or examining psychological functioning, interests, symptoms, defensive and coping styles, beliefs, attitudes, etc. Usually they are broadly focused. These vary tremendously based on the interviewer's skill, type of interview, and method of assessment. Structured interviews are rather like tests, with similar strengths and weaknesses. In fact, with computerized administration, the line between them is blurring.
Unstructured interviews are harder to evaluate.
Interviews and tests offer complimentary views and each may compensate for weaknesses of the other. Critics of tests frequently fail to realize that interviews are usually more subject to bias and naive errors.