DOES DIRECT TO CONSUMER ADVERTISING CHANGE CONSUMER CHOICES ABOUT PHARMACY ONLY MEDICINES? EVIDENCE FROM A DISCRETE CHOICE EXPERIMENT
Method: A discrete choice experiment (DCE) was developed to investigate consumer choices about management of a common health problem (cold sores), in which treatment options included pharmacy only and over the counter products. Respondents were asked how they would manage this condition, and then undertook the DCE. A novel aspect of the study was the inclusion of a short information style video advertisement promoting one of the product types (a pharmacy only anti-viral tablet) included in the experiment. Respondents were randomly allocated to one of three arms which varied in terms of the use of the advertisement. The control condition included the advertisement only at the end of the survey, whereas in the other two arms, respondents saw the advertisement either before they answered any questions about management of cold sores or before they undertook the DCE. The DCE included 16 choice sets with 3 product options and a no treatment option. Each option was described by a product brand label: antiviral tablet, antiviral cream, non-antiviral cream; and by the attributes: availability, frequency and duration of use, effectiveness, pharmacist recommendation and cost. Choices were analysed using a generalized multinomial logit model (G-MNL) and model estimates were used to predict product shares for each arm.
Result: A representative sample of 1500 consumers from an Australian on-line panel completed the survey. The results demonstrated a clear preference for cheaper products, more convenient administration and greater effectiveness. Responders who saw the advertisement before the DCE were more likely to choose the advertised product. Responses to additional questions about the advertisement indicated that consumers considered the advertisement had increased their knowledge of options available and the role of pharmacists in providing therapeutic information.
Conclusion: The project demonstrated the feasibility of using a DCE to estimate the impact of DTC advertising. This is important in determining policy about how therapeutic products are advertised, as in many countries, regulation of DTC advertising is strictly controlled, particularly for prescription and pharmacy only products.