Transparency in information about health
This dissertation comprises four manuscripts focusing on health risk communication and medical decision making. The first manuscript discusses differences, commonalities, and the applicability of three major approaches to help patients make better decisions: nudging, social marketing, and empowerment. The second manuscript presents results of an evaluation of media coverage about the HPV vaccine of newspaper and Internet reports in Germany and Spain. Based on predefined standards for
... ards for transparent, complete, and correct risk communication, the analysis revealed substantial shortcomings in how the media informed the public. The third manuscript centers on a standard format to communicate treatment benefits and harms: relative risk reductions and increases. Such formats have been found to misinform and mislead patients and health professionals. One suggestion is to always include information about baseline risk to reduce misunderstandings. Results show that even when baseline risk was communicated, it depended on the presentation format (percentage vs. frequency) and people's numeracy skills whether they correctly interpreted the risk reduction (or increase). Low numerates benefited from a frequency format, whereas high numerates performed better independent of the format. Yet, a substantial proportion of participants still misunderstood the meaning of a relative risk reduction (or increase). The fourth manuscript investigated how laypeople choose between medical treatments when ambiguity is present. One objection against communicating ambiguity is the claim that laypeople are ambiguity averse in the domain of gains and ambiguity seeking in the domain of losses. Results did not find supporting evidence for this claim in medical treatment choice. Moreover, most participants selected the same treatment option, independent of numeracy. However, the underlying choice strategies varied between individuals.