In marketing-speak, "opinion leaders" are people with a reputation who are likely to influence the buying behaviour of others.

In the field of medicinal products, "opinion leaders" are well-known or renowned doctors or other caregivers whose opinion is trusted by a large number of healthcare professionals, thus influencing their practice.

The strategic stakes are so high for pharmaceutical companies that they devote resources to managing opinion leaders, often through PR and marketing agencies whose role is to identify the opinion leaders in particular fields, assess their influence and contact them. Sometimes they are established opinion leaders, but sometimes they are also doctors who are not yet particularly influential, but the agencies will help build their reputations (by finding opportunities for them to publish, speak at congresses, etc.) and thus transform them into opinion leaders.

For a pharmaceutical company, opinion leaders' value is maximised when they attain an influential position, sitting on a committee of experts or editorial board, for example. The ultimate stage is when the opinion leader is promoted to an influential position within a university, or better still on a committee of experts for a drug regulatory agency.

Numerous academics have no qualms about accepting funding from pharmaceutical companies in exchange for their services, and even think they are doing good by accepting it to boost their research resources. But it is better to develop a clinical research capability that is independent of pharmaceutical companies.

In practice, the views of "leading professors" and other opinion leaders must be treated with scepticism and their conflicts of interests must be taken into account.

©Prescrire 1 June 2012

"Key opinion leaders: used as a marketing tool by drug companies" Prescrire Int 2012; 21 (128): 163-165. (Pdf, subscribers only).