Outcome

An outcome is the result of a process, action, or event. It denotes what happens after something occurs, and can be anticipated or observed after the fact. The term comes from the idea of something that comes out of a situation.

In probability and statistics, an outcome refers to a possible result of a random experiment. The set of all outcomes is the sample space; each outcome is a single element of that space. When the experiment is repeated, different outcomes may occur, and probabilities describe the likelihoods of these outcomes.

In research and medicine, outcomes are measures used to assess effects or safety. A primary outcome is the main result a study is designed to evaluate, while secondary outcomes are additional effects of interest. Outcomes can be quantitative (such as weight change, blood pressure) or qualitative (such as symptom improvement).

In policy, business, and project management, outcomes refer to the longer-term impacts or changes that follow an intervention, as opposed to outputs, which are the immediate products or services delivered. Outcomes may be intended or unintended and are subject to attribution challenges.

Interpreting outcomes involves consideration of timing, context, and uncertainty. Transparent reporting of how outcomes are defined and measured improves comparability across studies and programs.