07.01.08
A new study published in the April 9th issue of BMC Complementary & Alternative Medicine concludes that increased pharmaceutical advertising in a medical journal may be associated with publishing few articles about dietary supplements and publishing more articles with conclusions that dietary supplements are unsafe. “Because of the importance of established medical journals in informing and influencing professional and public behavior,” researchers said, “the question of unintended bias favoring advertisers in making editorial decisions is of great public health as well as business interest.” This is the first study of its kind to begin to explore the relationship between pharmaceutical advertising and the publication of articles about dietary supplements.
After reviewing one year of the issues of 11 major medical journals for advertising and content about dietary supplements, investigators found that total pages per issue ranged from 56 to 217, while advertising pages ranged from four to 88; pharmaceutical advertisements accounted for 1.5% to 75% of ad pages. Journals with the most pharmaceutical ads published no clinical trials or cohort studies about dietary supplements. Furthermore, the percentage of articles concluding dietary supplements were unsafe was 4% in journals with the fewest pharmaceutical ads and 67% among those with the most. The percentage of articles concluding that dietary supplements were ineffective was 50% higher among journals with more pharmaceutical ads.
As far as study limitations go, researchers only included a handful of the many medical journals available and used only the American library versions of these journals. However, the study did focus on those with very high readership that are often quoted by professional organizations, the media and policymakers. To support these findings, investigators believe additional research is needed to test alternative hypotheses in a larger sample of more diverse journals. In the meantime, they also say that these data should be used to support current efforts to reduce conflicts of interest in medical publishing and to make any such conflicts more transparent.
After reviewing one year of the issues of 11 major medical journals for advertising and content about dietary supplements, investigators found that total pages per issue ranged from 56 to 217, while advertising pages ranged from four to 88; pharmaceutical advertisements accounted for 1.5% to 75% of ad pages. Journals with the most pharmaceutical ads published no clinical trials or cohort studies about dietary supplements. Furthermore, the percentage of articles concluding dietary supplements were unsafe was 4% in journals with the fewest pharmaceutical ads and 67% among those with the most. The percentage of articles concluding that dietary supplements were ineffective was 50% higher among journals with more pharmaceutical ads.
As far as study limitations go, researchers only included a handful of the many medical journals available and used only the American library versions of these journals. However, the study did focus on those with very high readership that are often quoted by professional organizations, the media and policymakers. To support these findings, investigators believe additional research is needed to test alternative hypotheses in a larger sample of more diverse journals. In the meantime, they also say that these data should be used to support current efforts to reduce conflicts of interest in medical publishing and to make any such conflicts more transparent.