Comment When did peer review become anonymous?

Anonymous peer review is an important part of the process by which academic information is evaluated. Some of the problems associated with the process are discussed below. Although the history of peer review is well documented, there appears to be no record of when it became anonymous. Since most criticisms associated with the practice result from the anonymity of referees, this is significant. A number of well‐known and long‐established journals were approached in an attempt to determine when they adopted the process but none of the correspondents at the journals knew.