What is the definition of an endpoint in a clinical trial?

An endpoint in a clinical trial is fundamentally defined as a key safety or efficacy event of concern that is used to determine the effect of a treatment or intervention. This is crucial because endpoints serve as the primary outcomes that researchers measure to assess whether the treatment has a significant effect compared to a control. They provide a basis for evaluating the overall success of the clinical trial and are critical for regulatory submissions.

Endpoints can be classified into different categories, such as primary and secondary endpoints, which help in measuring both the main effects and additional outcomes of the intervention. The identification and definition of endpoints are a critical part of the trial design process, ensuring that they are relevant to the objectives of the study and appropriately measured through the trial's duration.

While the event chosen for statistical analysis could be interpreted as related to endpoints, it is more specifically tied to the results of the trial rather than defining what an endpoint itself is. The total number of patients treated is not an endpoint; it is merely a demographic or logistical detail of the trial. Lastly, the primary investigator's conclusion refers to the interpretation of data, which occurs after endpoints have been analyzed, rather than defining what an endpoint is.