Adherence means sticking to the treatment you are allocated. For example, if you are asked to take tablets as part of a trial, it’s about taking the right number of tablets at the right time, and, if appropriate, finishing the course.
Adverse events are undesired effects that may or may not be related to a treatment. For example, if you are given a drug to treat an illness and you become sick (e.g. dizziness, stomach ache or a rash), this would be described as an adverse event. If your sickness is caused by the drug, this would be called a side effect. Clinical trials will often look at both short- and long-term adverse events related to a treatment. Some adverse events may be serious and need to be reported to regulatory authorities (usually the MHRA or FDA).
All trials initiative
The AllTrials Initiative is an international movement that calls for all past and present clinical trials to be registered and their full methods and summary results reported. This increases transparency and reduces any potential ethical concerns regarding these clinical trials.