A measure of knowledge and confidence in relation to HIV and AIDS: reliability and validity.

Knowledge of HIV and AIDS is widely seen as an important determinant of anxiety about such infection in health care workers. However, existing measures of this knowledge suffer from a number of methodological problems and few demonstrate adequate reliability and validity. This paper documents the development of a new measure detailing its reliability and validity. Knowledge, and also confidence in knowledge, were assessed across seven domains of relevant information (e.g. epidemiology, personal risk, symptomatology) in one non-expert group (non-medical undergraduate psychologist) and in three groups with greater expertise (nursing students and third year and final year medical students). The measure was shown to be reliable and to discriminate between the four groups in a manner consistent with the level of education received by each group and in terms of both the scale scores for the seven domains and the individual items. In general, final year medical students were shown to be more knowledgeable, and more confident in their knowledge, than the other groups. The non-medical undergraduates showed the lowest level of knowledge. In general, the groups appeared under-confident in their knowledge about HIV/AIDS. This was interpreted in terms of members of these groups exhibiting caution and the perceived fluctuating nature of the HIV knowledge base. Implications for the training of health care workers in relation to HIV/AIDS are discussed.