he National Library of Medicine® (NLM®) is now involved in MEDLINE year-end processing activities. These include changing the Medical Subject Headings (MeSH®) on existing MEDLINE citations to agree with the 2005 version of MeSH, and other global changes such as changes to Supplementary Concept Substance Names. Check the NLM Technical Bulletin for an upcoming article about 2005 MeSH changes.
During end-of-year activities, NLM's schedule for adding indexed citations to MEDLINE and PubMed is temporarily interrupted. Once the end-of-year activities are complete (tentatively targeted for December 2004), the normal MEDLINE/PubMed update schedule will resume, and PubMed will use 2005 vocabulary in the MeSH translation tables and MeSH database, as well as in the citation data. According to the normal MEDLINE/PubMed update schedule, MEDLINE citations are released and revised Monday through Friday, and these citations are then available to MEDLINE licensees and PubMed users Tuesday through Saturday.
On November 17, 2004, NLM expects to halt temporarily the addition of new, fully-indexed MEDLINE citations to PubMed. NLM indexing staff will continue to index citations, but these records will be held and not added to PubMed until the normal update schedule resumes.
During end-of-year activities, "in-process" citations will continue to be added to PubMed. As a result, the number of PubMed records labeled [PubMed - in process] will temporarily increase. These citations do not have MeSH terms, but NLM performs issue level and subsequent citation level quality control reviews that are released to PubMed in advance of the MeSH headings being added.
A search limiting terms to fields affected by indexing (e.g., fibromyalgia [mh] AND review [pt]) does not retrieve in-process or publisher-supplied records (see list of fields added, changed, or supplemented during indexing). Therefore, during end-of-year activities when we are not adding completed, indexed citations to MEDLINE/PubMed, such searches - including those stored in the Cubby - may not retrieve new records for some weeks. To retrieve new, in-process records during this time, you should avoid limiting searches using search tags for affected fields. In this example, note that the search terms are not tagged: fibromyalgia review.
By December, the in-process citations that are within the scope of MEDLINE and that have been indexed since November 18, 2004 will be replaced as indexed citations with 2005 MeSH terms, Publication Types, etc. Searches, including Cubby Stored Searches, containing tagged search terms will then retrieve all applicable MEDLINE records.
Corrections on Hold
Also as of November 17, 2004, corrected citations for MEDLINE journals (e.g., because an author name was misspelled) will not be released to MEDLINE. NLM staff continue to correct completed citations and these will replace the incorrect citations in MEDLINE when the normal update schedule resumes.
Data (with search tags) added to MEDLINE records during indexing:
EC/RN Number [rn]
Grant Number [gr]
Note: Some grant numbers are added during indexing, but the majority are added at data creation time (when the citation is “in process” status).
MeSH terms [mh] (includes age groups; Human/Animal; Male/Female)
MeSH Major Topic [majr]
Publication Type [pt]
Subset [sb] (citation status values change from “In Process” to “MEDLINE” once MeSH indexing has been completed)
Substance Name [nm]
Note: English [la] is not on this list. Limiting to English language will retrieve in-process records.
By Sara Tybaert
MEDLARS Management Section
Tybaert S. MEDLINE®/PubMed® End-of-Year Activities. NLM Tech Bull. 2004 Sep-Oct;(340):e4.