Opinion Leadership - The Drug Study

The third influential study "introduced the notion of diffusion over time of a specific innovation through the social network of a community" (27, p. 21). The Drug Study was so titled because it was conducted to determine the ways by which doctors make decisions regarding the adoption of new drugs. All medical practitioners in four Midwestern cities were interviewed. Demographics and data about attitudes, prescription of drugs, exposure to information sources, and influence were collected. Additionally, questions were asked regarding the individuals the medical practitioners sought for advice, the ones they discussed their patient cases with, as well as the ones with which they socialized (27, p. 21). These questions were designed to identify opinion leaders within the communities.

This particular study introduced two additional elements: the acceptance of a new innovation (a new drug) and a record of diffusion over time (27, p. 21). In addition to the information provided by the decision-maker, the Drug Study used prescription records (objective data) to precisely pinpoint a doctor's first account of prescribing a new drug. The role of different influences was based on both the respondent's reconstruction of the event, as well as the inferences based on the "doctor's location in the interpersonal network mapped by the sociometric questioning of the entire community. Doctors could be classified according to their integration into the medical community, their influence on peers, their personal networks, their adoption of a new drug and the timing of the adoption, and all these measures could be interrelated" (27, p. 21-22).

Conclusions from the study supported opinion leadership theory. Colleagues were deemed more important sources of information than media sources, including professional journals. Furthermore, the more frequently a doctor appeared as part of the personal networks, the more likely hew was to be an innovative early adopter of a new drug. These findings support earlier studies, which highlight the impact of personal influence in the decision-making process (27, p. 22).

"In his review of the opinion leadership concept after the early studies, Elihu Katz suggested three criteria that distinguish leaders from non-leaders (27, p. 23):

1. Who one is - the personification of certain values by the opinion leader's figure,
2. What one knows - the competence or knowledge related to the leaders, and
3. Whom one knows - the strategic location in the social network."

The findings of these three early studies redirected communications research to focus not only on the impacts of mass media, but to further investigate the importance of personal influence in the flow of communication.