This blog post is from Lettie Conrad and Michelle Urberg, cross-posted from the The Scholarly Kitchen.
As sponsors of this project, we at Crossref are excited to see this work shared out.
The scholarly publishing community talks a LOT about metadata and the need for high-quality, interoperable, and machine-readable descriptors of the content we disseminate. However, as we’ve reflected on previously in the Kitchen, despite well-established information standards (e.g., persistent identifiers), our industry lacks a shared framework to measure the value and impact of the metadata we produce.
When Crossref began over 20 years ago, our members were primarily from the United States and Western Europe, but for several years our membership has been more global and diverse, growing to almost 18,000 organizations around the world, representing 148 countries.
As we continue to grow, finding ways to help organizations participate in Crossref is an important part of our mission and approach. Our goal of creating the Research Nexus—a rich and reusable open network of relationships connecting research organizations, people, things, and actions; a scholarly record that the global community can build on forever, for the benefit of society—can only be achieved by ensuring that participation in Crossref is accessible to all.
In August 2022, the United States Office of Science and Technology Policy (OSTP) issued a memo (PDF) on ensuring free, immediate, and equitable access to federally funded research (a.k.a. the “Nelson memo”). Crossref is particularly interested in and relevant for the areas of this guidance that cover metadata and persistent identifiers—and the infrastructure and services that make them useful.
Funding bodies worldwide are increasingly involved in research infrastructure for dissemination and discovery.
Preprints have become an important tool for rapidly communicating and iterating on research outputs. There is now a range of preprint servers, some subject-specific, some based on a particular geographical area, and others linked to publishers or individual journals in addition to generalist platforms. In 2016 the Crossref schema started to support preprints and since then the number of metadata records has grown to around 16,000 new preprint DOIs per month.
The Crossmark button gives readers quick and easy access to the current status of an item of content, including any corrections, retractions, or updates to that record.
Research doesn’t stand still: even after publication, articles can be updated with supplementary data or corrections. It’s important to know if the content being cited has been updated, corrected, or retracted - and that’s the assurance that publishers can offer readers by using Crossmark. It’s a standardized button, consistent across platforms, revealing the status of an item of content, and can display any additional metadata the member chooses. Crucially, the Crossmark button can also be embedded in PDFs, which means that members have a way of alerting readers to changes months or even years after it’s been downloaded.
With one click, you can see if content has been updated, corrected, or retracted, and access valuable additional metadata provided by the member, such as key publication dates (submission, revision, acceptance), authors’ ORCID iDs, content type, plagiarism screening status, and information about funding, license, peer review, and location of research data.
Additional Crossmark metadata is entirely optional, and determined by the member. We are not setting any particular guidelines for types of additional record metadata, although we expect that guidelines and best practices may emerge from within communities of interest or within disciplines. Learn more about the retraction guidelines published by the Committee on Publication Ethics (COPE).
For the purposes of Crossmark, there are two categories of updates: minor and major changes.
Minor changes include correcting formatting and spelling. There are no substantive changes you would need to alert the reader to, so the Crossmark status is current. If changes don’t affect the crediting or interpretation of the work, the Crossmark status remains as it is. This also applies to article versioning - if the changes between versions of a work don’t reflect major changes in the content of the paper, keep the Crossmark status as current.
Major changes affect the Crossmark status of the work, as Crossmark is geared towards letting readers know about significant changes to the published literature. Substantial changes, such as the retraction of an article due to an error, or the addition or removal of an author, should be reflected in a work’s Crossmark status. It is good practice to publish a notice of correction or retraction (with its own DOI) and not put it behind access control. This allows readers to follow the link in the Crossmark button and find further details about the update.
Watch the introductory Crossmark animation in your language:
Members can reassure readers that they’re keeping their content up-to-date and showcase additional metadata.
Researchers and librarians can easily see the changes to the content they are reading, find out who funded the research, what licenses apply to the content, and more.
Anyone can access the Crossmark metadata through our REST API, providing a myriad of opportunities for integration with other systems and analysis of changes to the scholarly record.
Evidence of trust
Crossmark is recognizable across all content, and gives members a way to provide evidence to readers of why they should trust the content; so they can use it and cite it with confidence.
Anyone can access the Crossmark metadata through our public REST API, providing a myriad of opportunities for integration with other systems, and analysis of changes to the scholarly record.
How Crossmark works
Members place the Crossmark button close to the title of an item of content on their web pages and in PDFs, and commit to informing us if there is an update such as a correction or retraction, as well as any additional metadata. They can also customize the popup box to include other signs of editorial rigor, such as the type of peer review used, whether the document was screened for originality using Similarity Check, and more. Version of record copies that are hosted by third parties can also display the Crossmark button.
The presence of a Crossmark button on a content item doesn’t by itself indicate that the document is up-to-date, but it shows that the publisher is maintaining the document somewhere. When a reader clicks on the button, a pop-up box appears that shows the current status of the content (up-to-date, updates available, or retracted), a persistent link to the publisher-maintained copy, and any additional information.
It’s important to apply the Crossmark button to all of your current content, not just content that has updates. The problem with partial implementation of Crossmark is that when an item of content is published you won’t know if it might need to be updated at some point in the future. Therefore, a researcher may download a PDF article today without a Crossmark button, but if the article is subsequently updated and the Crossmark button is added, the researcher has no way of knowing if their locally-saved article is still current, as it had no Crossmark button at the point when they downloaded it.
It’s also good practice to show the Crossmark button on all your content, to show readers that you are participating in Crossmark, and that they can check your content for updates through the button.
We encourage members to implement Crossmark for backfile content as well as current content, but doing so is optional. Even if you do not intend to implement Crossmark across your complete backfile, we encourage you to do so for archival content which has updates.
Obligations for Crossmark
As a member participating in Crossmark, you agree to:
Maintain your content and promptly register any updates
Include the Crossmark button on all digital formats (HTML, PDF, ePub)
Implement Crossmark using the script provided by us
Not alter the Crossmark button in any way other than adjusting its size.
There are no additional fees to participate in Crossmark.
How to participate in Crossmark
Members participate in Crossmark by registering and assigning a DOI to a Crossmark policy statement. They then add a snippet of code to their landing pages and PDFs. This generates the Crossmark button and popup. The policy statement is a page on their website, which explains their participation in the service, their commitment to maintaining versions of any record that displays the Crossmark icon, and their policies on corrections, retractions, withdrawals, and other updates.
The minimum requirement for Crossmark metadata is:
To see which Crossref members are registering Crossmark information, visit Participation Reports. These reports give a clear picture for anyone to see the metadata Crossref has including Crossmark data.