Intramural Funding Designation in the MEDLINE/PubMed Grant Number Field

[Editor's note: On April 8, 2015, the title of this article was changed to clarify the meaning.]

[Editor's note, June 12, 2015: For updated information on intramural funding designations, please see Granting Organization Designations: Addition of Intramural NIST as a Funding Source and NCCAM Name Change.]

[Editor's note, August 27, 2015: Additional information available in the article, Intramural NIH Research Support: Status of Publication Type [PT] and Grant Number [GR] Elements.]

The National Library of Medicine (NLM) is updating the format of NIH intramural funding in the Grant Number (GR) field found in MEDLINE/PubMed records. Intramural funding is associated with articles in which the research is performed by employees of NIH. This new format makes intramural support for published articles clearer to users by including "Intramural NIH HHS" in the GR string.

Currently, two conventions are used in the GR field to indicate NIH Intramural research support:

1. An official Z prefix grant number, and
2. An unofficial Z99 prefix grant number (introduced by NLM several years ago).
   
   

The Z99 notation was added to the Grant Number string for PubMed records with NIH intramural support in cases where the manuscript was deposited in the NIH Manuscript Submission (NIHMS) system. The Z strings overlap with the Publication Type (PT) "Research Support, N.I.H., Intramural" for MEDLINE-indexed articles. For non-MEDLINE papers, the grant occurrence is the primary indicator of intramural support in PubMed.

However, the Z99 notation is not intuitive and few people know what it represents. As a result, we are transitioning from relying exclusively on the Z project number for identifying NIH intramural support to an explicit phrase in the funding agency name.

For example, the old GR string:

Z99 EY999999/EY/NEI NIH HHS/United States

. . .will be replaced with a new GR string:

Z99 EY999999/Intramural NIH HHS/United States

PubMed users who wish to search at a more granular level than “Intramural NIH” will still be able to use the 2-letter NIH Institute & Center (IC) code in the Z project number, as available. Using the example above, this PubMed search:

ey [gr]

. . .will still retrieve PMID 25218043 that initially had this GR string:

Z99 EY999999/EY/NEI NIH HHS/United States

NLM has been using the new intramural GR string format for prospective citations for which the data come from the NIHMS for a short time now. This updated intramural format is effective for all retrospective citations, effective March 26, 2015. NLM is also investigating how we might synchronize the GR Intramural NIH indication with the Publication Type value of “Research Support, N.I.H., Intramural.” Right now, both should be searched for comprehensive retrieval since 2005; for example:

intramural nih [gr] OR research support, n.i.h., intramural [pt]

Going forward, the same format for denoting intramural support will be used for other agencies that are identified as funders in a PubMed record as the information becomes available. To date, the agencies, other than NIH, with formal policy announcements about participating in the NIHMS and that will have an intramural designation include:

Intramural AHRQ HHS

Intramural CDC HHS

Intramural FDA HHS

Intramural VA

Please refer to the NLM Web resource page for explanations for both the grant number 2-letter codes and the agency acronyms.