Improving depiction of benefits and harms: analyses of studies of well-known therapeutics and review of high-impact medical journals.

The issues of weighing benefits and harms and of shared decision-making have become increasingly important in recent years. There is limited knowledge and lack of adequate data on the most transparent method of communicating the information. In this article we discuss examples of communicating benefits and harms for well-known therapeutics, illustrating that relative risk estimates are not helpful for communicating the chance of experiencing adverse events. In addition, we show that asymmetric presentation of the data for benefits and harms is likely to bias toward showing greater benefits and diminishing the importance of the harms (or vice versa). We also present preliminary results of a brief review of high-impact medical journals that show limitations of current systematic reviews. In the review we found that every second published study does not discuss frequency data and 1 in 3 studies that report information on both benefits and harms does not report information in the same metric. We conclude that consistently depicting benefit and harm information in frequencies can substantially improve the communication of benefits and harms. Investigators should be requested to provide frequency data along with relative risk information in the publication of their scientific findings. Currently, even in the highest impact medical journals, evidence of benefits and harms is not consistently presented in ways that facilitate accurate interpretation.