A study of the claims made in pharmaceutical advertising has sparked a call for more control to protect prescribers and patients.
Published today in the New Zealand Medical Journal, the University of Otago study looked at advertisements in industry magazines New Zealand Doctor and Pharmacy Today.
One third of the claims in the advertisements had no supporting evidence, and 35% cited at least one randomised controlled trial.
''A high proportion of pharmaceutical advertisement failed to meet New Zealand regulatory requirements that claims `are valid and have been substantiated','' the study said.
When a trial was cited, its conclusions did not always match the claim made in the advertisement. Senior author Dr Lianne Parkin said many doctors and pharmacists were unlikely to have the time to check the accuracy of claims.
The study also found the trials cited were heavily weighted towards those with industry sponsorship (78%).
''Our overall findings are consistent with concerns internationally that the therapeutic claims made in some advertisements are not supported by good evidence and might have a negative impact on what doctors prescribe,'' Dr Parkin said.
The study looked only at industry magazines. New Zealand is one of only two countries in the world that allow direct to consumer advertising in mainstream media.
''Our findings do suggest a need for greater monitoring of pharmaceutical advertising in New Zealand,'' the researchers concluded. Their call is backed in an editorial also published in the medical journal today, written by Otago University academics Prof Les Toop and Associate Prof Dee Mangin.
''Given the widespread publicity around misleading marketing, it might be hoped readers of the magazines containing these advertisements would pay little or no attention to them.
''However, the industry's market research suggests otherwise, as do studies of the negative influences of marketing on prescribers,'' they write.
The public often assumed that the advertisements were carefully vetted and checked, but that was not the case.
''There is little regulatory control to counter these influences.
The self governing Advertising Standards Authority in New Zealand, and the self monitoring codes of practice - designed and policed by industry - are both lax, and complaints and sanctions rarely applied,'' the editorial says.
Drug advertising study
• Study looked at trade magazines read by doctors and pharmacists
• Researchers looked at all pharmaceutical advertisements in one year
• A third of the therapeutic claims cited no supporting evidence
• High proportion of trials cited were industry sponsored New Zealand unusual in also allowing drug advertising to general public
