AUTHOR:  N. Tredoux

ABSTRACT: With the current population norm group for the Occupational Personality Questionnaire at almost 55000 people, this is one of the most widely-used personality questionnaires in South Africa. This chapter will give an overview of the development of the Occupational Personality Profile and the rationale for the various scales. A brief historical review of reliability and validity studies in South Africa will be discussed, and the different norm groups available for the test will be compared.  In the context of fairness and best use, the relationship between the reliabilities of the OPP scales and the home language, race and educational level of the respondents will be discussed. Age groups and sexes will also be compared. The groups will also be compared in terms of their mean scores on the OPP scales. This leads us to the question of whether one should use a group-specific norm or a general population norm, and how to decide between the options.  A discussion of differential item functioning for race and language groups will follow.   Some attention will also be given to the decision of whether the Occupational Personality Profile is suitable for an intended respondent, or whether a different means of assessing personality (which need not be a questionnaire) should be employed.  The different delivery methods of the OPP, and the available computer-generated reports will be discussed, with the emphasis on using technology to facilitate the fair and appropriate use of the questionnaire. The use of the Occupational Personality Profile for assessing competencies will be discussed, as well as the implications of automating this process. Special emphasis will be placed on the importance of doing an integrated assessment and not relying on one source of information only.