The two principal methods of gathering data, the questionnaire and the interview, both have advantages and disadvantages, and each method can tell very distinct things about a person.
The questionnaire generally the least costly method of gathering information, (Ivancevich, 2010) and is a good way to obtain a large amount of information in the shortest amount of time. It is used primarily to gauge how the respondent answers the questions, in order to develop a basis for forming a judgment about the individual. However questionnaires limit information gained to the respondent’s prepared answers. Often it is not what you say, but how you say it. By being limited to reading responses, important information can be missed.
The interview is probably the most common way of gathering information for job analysis (Ivancevich, 2010). It allows the analyst to not only ask and receive answers, but also observe body language and listen to voice inflection and other audible ques. The additional information that can be gathered by listening and observing are not possible with a questionnaire. However interviews can be difficult to standardize. Different interviewers can ask the same questions in different ways, and can unintentionally lead the interviewee, causing them to give a different answer than they would have otherwise.
I believe that by combining both methods, it is possible to gain a more accurate, beneficial assessment of the individual's attitudes, qualifications, and potential fit for the job analysis.
Ivancevich, J. M. (2010). Human Resource Management, 11th Edition. Boston: The McGraw-Hill Companies, Inc.
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