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Drug Promotion - What We Know, What We Have Yet to Learn - Reviews of Materials in the WHO/HAI Database on Drug Promotion - EDM Research Series No. 032
(102 pages)

Table of Contents
View the documentAcknowledgements
View the documentExecutive summary
Open this folder and view contentsIntroduction
Open this folder and view contentsReview 1. What attitudes do professional and lay people have to promotion?
close this folderReview 2. What impact does pharmaceutical promotion have on attitudes and knowledge?
View the document2.1 Reported use of promotion as a source of drug information
View the document2.2 Reported use of promotion as a source of information in adopting new medicines
View the document2.3 Impact of promotion on self-reported attitudes and knowledge
View the document2.4 Research designs that aim to avoid the limitations of self-report data
View the documentSummary of conclusions
View the documentDirections for future research
Open this folder and view contentsReview 3. What impact does pharmaceutical promotion have on behaviour?
Open this folder and view contentsReview 4. What interventions have been tried to counter promotional activities, and with what results?
View the documentFinal conclusions
View the documentReferences

Review 2. What impact does pharmaceutical promotion have on attitudes and knowledge?

Many descriptive studies clearly show that much promotional material contains inaccuracies, or at least presents very selective accounts of the evidence about the drug presented62,63,64. The question this review addresses is whether and how far promotion (including these inaccuracies and biases) affects the attitudes and knowledge of those who are exposed to it.

Very little research has looked specifically at the effect of promotion on attitudes, much more has examined the effect of promotion on knowledge. The studies here are part of a field of research into the determinants of prescribing - how doctors learn about drugs, and how they come to prescribe new products.

Most of the studies discussed in this review are really about how much doctors report using promotion as a source of information (either for all drugs, or particularly for new drugs) rather than about effects of promotion on attitudes or knowledge. They are included because they provide information relevant to the question of whether promotion affects prescribers’ knowledge.

Some studies look directly at the impact of promotion on attitudes and knowledge, by using an experimental approach65, by interviewing people about previous exposure66, or by following up participants in a promotional event67. Others approach the question in a more sophisticated or indirect way. Ziegler et al.62 look at whether doctors notice and remember errors in promotion. Sansgiry et al.68 look at whether consumers are aware of information missing from advertisements. Others63,64 look at doctors’ attitudes or knowledge in areas where there is disagreement between commercial and scientific information and infer the impact of promotion from this. Ferry et al.69 directly assessed knowledge of prescribing for the elderly and looked at it in relation to self-assessed reliance on promotion.

The methods that have been used in this area are not capable of producing certainty about causal relationships. Firstly both exposure to promotion, and knowledge and attitudes about drugs, are often assessed using self-report data. Secondly the relationship between them is often also assessed using self-report. That is, doctors are asked how much their prescribing is influenced by promotion. Self-report can be misleading when doctors’ beliefs are inaccurate (e.g., they may believe that they are exposed less often than they are), or when their answers to questions are biased towards being more socially acceptable than what they really believe.

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Last updated: May 4, 2012