Background: Any therapeutic intervention carries with it the potential for benefit and harm. Generally, benefit is far more common than risk; however, risk aversion drives many of the treatment decisions made by patients and their physicians.
Objective: To provide guidelines to help clinicians improve their understanding of causality and the interpretation of harm.
Methods: A group of dermatologists involved in data safety monitoring boards, clinical trial investigators, and a clinical epidemiologist identified the need for practical advice on how to understand and explain causality and harm and combined to share their knowledge.
Results: An explanation of how data are collected and the environment that shapes the data seen by clinicians is presented. The article spans an overview of the regulatory environment that informs trial design for regulatory approval to a description of types of designs that inform safety and techniques, such as the rule of three, to provide guidance to clinicians in interpreting the data.
Conclusion: Communicating the potential for harm to patients is critical. Placing the potential for rare and serious risks into perspective for the patient is as important as discussing the potential benefits of medication.