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6.5.2  Which fields to download

In addition to the full record citation, a number of key fields should be considered for downloading from databases where they are available. Further detailed guidance on which fields to download has been compiled by the Trials Search Co-ordinators' Working Group and is available in a document entitled TSC User Guide to Managing Specialized Registers and Handsearch Records, available at:


Abstract: abstracts can be used to eliminate clearly irrelevant reports, obviating the need to obtain the full text of those reports or to return to the bibliographic database at a later time.

Accession number / unique identifier: it is advisable to set aside an unused field for storing the unique identifier / accession number of records downloaded, such as the PubMed ID number (PMID). This allows subsequent linkage to the full database record and also facilitates information management such as duplicate detection and removal.

Affiliation / address: may include the institutional affiliation and / or e-mail address of the author(s).

Article identifier / digital object identifier (DOI): can be used to cite and link to the full record.

Clinical trial number: if the record contains a clinical trial number such as those assigned by the or ISRCTN schemes or a number allocated by the sponsor of the trial, these should be downloaded to aid linking of trial reports to the original studies. An example of this is the Clinical Trial Number (CN) field recently introduced in EMBASE. 

Index terms / thesaurus terms / keywords: see Section 6.4.5. These help indicate why records were retrieved if the title and abstract lack detail.

Language: language of publication of the original article.

Comments, corrections, errata, retractions and updates: it is important to ensure that any fields that relate to subsequently published comments, corrections, errata, retractions and updates are selected for inclusion in the download, so that any impact of these subsequent publications can be taken into account. The most important fields to consider, together with their field labels in PubMed, are provided in Box 6.5.a.