Peer review is the evaluation of work by one or more people with similar competencies as the producers of the work. It functions as a form of self-regulation by qualified members of a profession within the relevant field. Peer review methods are used to maintain quality standards, improve performance, and provide credibility. In academia, scholarly peer review is typically used to determine an academic paper's suitability for publication. The reviewers are experts in the topic at hand and anonymous. Peer review can be categorized by the type and by the field or profession in which the activity occurs, e.g., medical peer review. It can also be used as a teaching tool.