ABSTRACT
During clinical studies, patients always have undesirable experiences. These may or may not be related to the study drug or device. These experiences are known as adverse events (AEs) or adverse experiences and may be considered adverse effects or adverse drug reactions if there is a relation to the treatment. The strict definitions of what is an adverse event (AE), an unexpected AE, and a serious adverse event (SAE) are found in the Code of Federal Regulations (21 CFR), the European standards (EN), and International Standards (ISO). Data managers typically do not make judgments about what is an adverse event and what is a serious adverse event, but they do need to understand enough about the data to process and store them properly.
