Background: While direct-to-consumer (DTC) medical advertising can provide useful information, it also risks oversimplification and being misleading. For an abbreviated prostate cancer treatment regimen called "ultrahypofractionation" (UHF), advertising has been used for CyberKnife (CK), a common delivery system for stereotactic body radiation therapy. We hypothesized that those viewing an advertisement for CK versus factual information would have inaccurate impressions of effectiveness and safety.
Methods: 400 men aged 40-80 were randomly assigned to one of four arms: a de-identified CK advertisement, the same advertisement with disclaimers, scientific information obtained from review of contemporary peer-reviewed literature, and a control. Subjects answered questions regarding risks/benefits of CK and likelihood of pursuing CK versus other treatments. Regression analysis was performed to determine factors associated with CK preference.
Results: 400 men were included. Compared to controls, those who viewed any of the three interventions were more likely to pursue CK over other treatments (p < 0.01), with a greater increase in the advertisement groups. Respondents who viewed scientific information were less likely to agree CK is superior regarding impotence and urinary dysfunction. Disclaimers decreased positive impressions of CK's side effects, but not effectiveness. Both advertisement and advertisement with disclaimer respondents were more likely to consider CK superior.
Conclusions: DTC medical advertisements can be misleading and impact laypersons' impressions. In this case, viewing an advertisement created inaccurate impressions regarding effectiveness and safety of UHF for prostate cancer.