The PSI ratifies standards via a mechanism called the Document Process 13 (DocProc). The DocProc is a formal process by which a proposed specification is thoroughly reviewed and refined before becoming an officially ratified standard of the PSI. Once a draft specification has been prepared by a working group, the process begins with the submission of a proposed specification to one of the PSI editors who has not been involved in the development of the specification. If the specification is deemed ready by the editor, it is sent to the Steering Group for a 14-day internal review period to assess initial suitability. Steering Group comments are then addressed by the proposers and the revision is resubmitted. Next, the editor selects at least two external reviewers familiar with the subject matter but not part of the development of the standard. The peer reviewers are generally anonymous, although there is precedent for reviewers requested to be listed in acknowledgements in recognition of their often-substantial time spent reviewing a specification. The specification is then revised based on the comments of the reviewers, after which the revision is subjected to a 4-week open community commenting period during which the proposal is widely advertised as a nearly complete standard and any additional comments from the community at large are sought. Ultimately when all comments received have been addressed to the satisfaction of the handling editor, the specification is declared ratified as an official PSI standard. The DocProc may be revised with the approval of the Steering Group, and has undergone several revisions in the past 20 years. The current version 1.1.2 is available at the PSI web site at . It is common that a journal article describing the standard in brief is prepared, submitted, and reviewed independently (ideally in parallel to the PSI review process) by a journal and generally, the standard is not declared ratified until both the DocProc review and journal review are complete.