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Open Science

What are PIDs and how do they benefit scholarly communication?

Metadata | Open Source | Persistent identifiers
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"PIDS are useful because they act as pointers to an output and enable connections between different research outputs and people and organizations..."

Persistent identifiers (PIDs) are unique references that help identify researchers, research, institutions and digital objects such as software and datasets. The ‘persistent’ in PIDs is due to the fact that even if the object they identify is moved or changed the PID will continue to resolve to the same object. This ensures traceability – that digital objects can be easily located and accessed over time – and that researchers and institutions can be uniquely identified and not confused with others that share similar names.

Hindawi currently uses three main types of open PIDs: DOIs for research, ORCIDs for researchers, and RORs for institutions.

What is a DOI?

A DOI is a Digital Object Identifier. DOIs identify scholarly articles or versions of articles, as well as other research outputs such as preprints and datasets. In scholarly communication, infrastructure organizations such as Crossref and DataCite provide formal registration for DOIs for the literature and data respectively. This helps humans and machines keep track of outputs and ensures you are able to find or link to a specific piece of research or data even if the infrastructure around that digital object changes in future. This helps with discoverability, accessibility, and persistent citations of research and this in turn helps with accountability, verifiability, and reproducibility.

Learn more about DOIs >>

What is an ORCID?

ORCID stands for Open Researcher and Contributor ID. It is unique identifier for researchers and other contributors to the scholarly record. They help researcher disambiguation – distinguishing researchers who share the same name but also forms a living record of your professional activities and scholarly contributions, and connects you to your institutions and funders.

ORCIDs help accountability and authentication of research outputs and assists funders, publishers, and other organizations in maintaining an accurate record of who did what, when, and where. You can use your ORCID to build your professional reputation and improve discoverability of your work and achievements. Make sure you only have one ORCID and keep it updated with your current affiliations as this helps institutions and publishers trust and verify you are who you say you are.

Learn more and register for an ORCID here >>

What is a ROR ID?

A Research Organization Registry, or ROR, uniquely identifies research organizations such as universities, institutions, and hospitals. They are useful in accurately tracking and monitoring researcher affiliations. While we could ask three researchers at a university for their affiliation and get three slightly different answers, a single, unambiguous, standardized ROR identifier enables people and systems to immediately recognize a shared affiliation. ROR IDs, alongside DOIs and ORCIDs, can also help institutions more accurately measure their own research outputs.

Learn more about ROR >>

What are the challenges?

PIDS are useful because they act as pointers to an output and enable connections between different research outputs and people and organizations. These connections, or PID Graph, can then become a source of information and knowledge in itself that researchers can use for discovering connections between topics or to find opportunities for collaboration.

Because they are persistent across multiple platforms and workflows and can be used by funders and institutions as well as publishers, they can also ultimately reduce the administrative burden on researchers in reporting about their outputs and activities (such as removing the need to fill in duplicate information for a grant proposal and when submitting an article). But this added value relies on them being openly available, adopted by different stakeholders, implemented and used appropriately and that the information associated with them - the metadata – is also open as well as being accurate and of a high quality.

“There is no Open Science without open metadata”

‘Open funding metadata through Crossref:…’, Crossref

Open and Commercial PIDs

Ensuring the persistence of these identifiers and their underlying metadata requires open data and infrastructure. Identifiers persist only as long as the organization that manages them supports them. Some commercially run PIDs hold their data privately, so if these organizations fail the data supporting the PIDs may no longer be maintained or disappear. However, many PIDs are created and operated by collaborative initiatives working within a framework for open infrastructure. This ensures that if an organization fails, the metadata behind the PIDs will be available to the communities that need them, to use or maintain as needed.

ROR’s Remit

ROR IDs only reference institutions at the highest level, so while a university will likely have a ROR, departments and affiliated hospitals of that university will not have a separate identifier and will be referenced under the same university ID. While commercial competitors to ROR do offer higher levels of disambiguation, ROR’s model is openly and freely available and is the default organizational ID for many other emerging scholarly infrastructures and increasingly given priority in progressive funder and institutional policies for Open Science.

Ghost ORCIDs

While having and maintaining your ORCID can help traceability and author disambiguation, and thus ensure the right person gets credit for their work, it’s important that you only have one and it is up to date. Ghost ORCIDs are IDs that are created and then left empty. These may have been created legitimately, for example, to meet a submission requirement, but in some cases may be created to introduce fake elements or otherwise abuse the system. Poorly maintained, faked, or unverifiable ORCIDs reduce the overall trust in ORCIDs and in researchers. If you have one, keep it up to date; if you have more than one, deactivate your duplicates; and if you’re not sure, check your ORCID here.


Although DOIs, RORs and ORCIDs are the most commonly used open identifiers there are alternatives, including some well-established, discipline-specific identifiers. Lack of standardization, however, means the same information may exist across multiple systems using different IDs. While standardization may seem like the ideal outcome to preserve all records, there is not yet an international and shared agreement about the specific PIDs adopted as part of a coherent scholarly infrastructure. However, National funding organizations and national governments are now starting to look at this problem, including PID requirements in their OA policies and supporting the work done, for example, by the Research Data Alliance (RDA) National PID Strategies Working Group.

How can we work together to maintain the integrity of PIDs?

When you publish with us we will register your work with a DOI, ensuring your work is interconnected and clearly identifiable. During submission we require the corresponding author of an article to provide their ORCID, although we strongly encourage all authors to do so in order to make the most of the individual benefits this can provide. We will also ask that researchers choose their affiliations from a prepopulated list where possible – these institutions are linked to ROR IDs and so ensures consistency and reliability of institutional data (where free text might lead to many names being used to refer to the same institution).

PIDs support preservation and accessibility of research and using them can save you time and effort while improving the data on the scholarly record, and in turn helps us improve our understanding of it.

This blog post is distributed under the Creative Commons Attribution License (CC-BY). Illustration adapted from Adobe Stock by David Jury.

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