Journals have built policies that vary widely across the six fundamental aspects of OA – reader rights, reuse rights, copyrights, author posting rights, automatic posting, and machine readability. This, in turn, has caused confusion among authors seeking to make informed publishing decisions, funders seeking to formulate and enforce their access policies, and other stakeholders within the research ecosystem. The HowOpenIsIt? Open Access Guide created by SPARC, PLOS, and OASPA consolidates the key elements of journal policies into a single, easy-to-follow resource

"one page summary of “Paywall the movie” documentary by Jason Schmitt" by Dasapta Erwin Irawan is licensed under CC BY 2.0.

When evaluating the full impact of an OA publication, you may want to consider using altmetrics in addition to the traditional bibliometrics that are sometimes used to gauge an article's impact. Altmetrics capture how articles are viewed and shared on social media, blogs, the news, etc.

Popular metrics such as h-index or impact factor don't provide a full picture of an article's use, yet they are widely applied in academic tenure and funding decisions
The quantification and oversimplification of research impact harms all scholarly disciplines by creating adverse effects, such as self-plagiarism, gratuitous self-citation and honorary authorship. Learn more about metrics at Scholcommlab, which seeks to support researchers and research administrators to develop knowledge that empowers individuals to recognize, interpret, critically assess and effectively and ethically use scholarly metrics.

For more information, see our Research Impact and Evaluation guide.