What is a persistent identifier? 

A persistent identifier (PID) is a long-term identifier for resources such as articles, datasets, people, and many other resources. PIDs are crucial for enabling the reliable citation, sharing, and discovery of digital resources, as they allow users to find and access the exact version of an object, even if its location, format, or ownership changes over time. 

Links to specific webpages on the internet are easily broken by changes to URL schemas.  

In a 2013 article in the Atlantic, almost half of all the webpages cited in US Supreme Court opinions were already broken. The percentage of links in the original study that are broken is probably higher now a decade later, and the link we used in the previous sentence will also one day break because the Atlantic does not use a persistent identifier for its articles. The blog that the Atlantic cites also does not use persistent identifiers, but still works due to an unchanged URL schema. The eventual academic article that was published by the blog authors does have a persistent identifier, a doi.org link, which will make the academic article referenceable for a very long time.  

What persistent identifiers can researchers use for their research? 

Digital Object Identifier (DOI) 

A DOI is a unique alphanumeric string assigned to a digital object, such as a journal article, dataset, or software, to ensure its long-term accessibility and traceability. 

DOI.org links are generated by a publishing organization (which can include traditional publications such as journals or books, but also data repositories such as YoDa and Zenodo) using a prefix assigned to them by a DOI registration authority. The publisher then sends the generated link to the registration authority, who will then add the new resource to the DOI resolution system. If the publisher updates their URL format for their website, they update the DOI resolver with the new scheme.  

ORCiD 

ORCID (Open Researcher and Contributor ID) is a persistent identifier system designed to uniquely identify researchers and contributors and to connect their research activities across disciplines, institutions, and geographic borders. ORCID provides a unique digital identifier, an ORCID iD, for individuals to use throughout their academic and professional careers, allowing them to distinguish their work from that of others with similar names and to connect their contributions to a single, persistent record of their research activities. 

ORCID iDs are widely used by publishers, funders, research institutions, and other stakeholders in the scholarly ecosystem to streamline workflows, reduce administrative burden, and enhance interoperability among research systems. ORCID iDs can be integrated with many research information systems, including manuscript submission systems, grant application platforms, and researcher profile systems, allowing for automatic updates and linking of research outputs. 

ORCID is a non-profit organization that is governed by a board of directors, and its services are freely available to all researchers worldwide. 

ResearcherID 

ResearcherID is a unique identifier assigned to researchers by Clarivate Analytics, allowing them to manage their publication record and track their citation metrics. Due to the integration of ORCID number and ResearcherID, the Web of Science Core Collection assign them to the Author Identifiers index, enabling researchers to get access to numbers of profiles and publications. 

Scopus ID 

A Scopus ID is a unique identifier assigned to each author profile in the Scopus database. It is a 13-digit number that is assigned to an author when they publish a paper in a journal that is indexed by Scopus. The Scopus ID allows for easy and accurate tracking of an author’s publications and citations, and is often used to evaluate research productivity and impact. Researchers can use their Scopus ID to create an author profile in Scopus, which includes a list of their publications, citation metrics, and other relevant information. 

What is their importance/benefits for your research? 

Persistent Identifiers are important for creating and maintaining links between objects, people and infrastructure. Thye can ensure that people cannot be referred-redirected to ambiguous entities, by pointing persistently on a specific location of a digital object. Without the use of PIDs, the so-called “broken links” issue which leads to web access errors (i.e., HTTP errors) cannot be resolved. 

The use of PIDs makes your research work: 

• Discoverable, by identifying it uniquely. 
• Accessible from others, through a consistent resolvable link, even if the initial location changes. 
• Interoperable as they provide transparency, making your work more trustworthy. 
• Reusable as they point directly to a specific version of your work. 
• Citable, by facilitating the citations of it through resolvable links.  
• Assessable, as an interrelated-interlinked network of your research, can facilitate the evaluation of it and increase your impact as a researcher.