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Cataloging and Metadata Management

Guidelines for Serial Treatment at NLM



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1. What is a Serial?

A serial, as defined by the Anglo-American Cataloguing Rules, 2nd edition, 2002 Revision (AACR2R), is a publication in any medium:

  • Issued in a succession of discrete parts
  • Generally bearing numerical or chronological designations
  • Having no predetermined conclusion

At NLM, serials include journals, periodicals, newspapers, and annuals (reports, yearbooks, etc.).


On Series t.p.:

  • Medizin aktuell, 001-
  • Occupational injuries and illnesses in New Mexico, 1977-
  • Directory of preferred provider organizations, 1st. ed. (June 1983)-

The numeric or chronological designation should appear prominently in a formal statement. Exceptionally, a designation may be taken from an informal statement (e.g., in the text of the preface) if there is conclusive evidence that the title is a serial, such as a statement of intent to continue indefinitely, a statement of frequency in the title, or, retrospectively, evidence that the title has been published in frequently issued editions.

2. Distinguishing a Serial from a Single or Multipart Monograph or Integrating Resource

  • A single monograph is an item complete, or intended to be complete, in one part.
  • A multipart monograph (work-in-parts) is a monograph complete, or intended to be complete, in a finite number of separate parts.
  • When there is no explicit statement of intent to publish indefinitely, a judgement must be made whether an item is a serial, a single monograph, or a multipart monograph, since means of acquisition and cataloging treatment differ for the different types of publications. The judgement is based, in part, on subject matter and takes into consideration whether or not it is likely that such a topic could be discussed indefinitely. Other criteria for judgement include time restrictions (e.g., a series of annual reports for a finite project, such as the implementation of a five-year plan, are treated as separate monographs, while a series of publications emanating from a single event constitutes a multipart item), etc.
  • An integrating resource is a resource that is added to or changed by means of updates which do not remain descrete and are integrated into the whole, such as a loose-leaf or Web site.

3. Determining the Intention to Publish Indefinitely


  • Titles that imply continuation (e.g., Advances in ... ).
  • Items with a statement of frequency or a numeric or chronological designation in the title.

    Use caution in applying this criterion. These same designations may appear on a one time report, on multipart items emanating from a single event, or on sequentially issued publications from a project with a finite duration.

  • Items which can be purchased on a continuing subscription order, though multipart items are also occasionally available by subscription.
  • Items with ISSNs are generally, but not always, serial publications. Even when an ISSN is present, all other criteria must be met before it can be assumed that a publication is a serial.
  • When in doubt, consider a publication to be a multipart item, rather than a serial.

Note that even though a title meets all criteria for a serial publication, an individual institution may decide not to treat it as a serial.

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4. Kinds of Publications Treated as Serials at NLM

In general, NLM follows Library of Congress practice, as outlined in Library of Congress Rule Interpretations (LCRI) 12.0A.

4.1. Numbered Monographic Series

A monographic series is a group of separate items where each item bears an individual title as well as a collective title, common to the group. Monographic series are classed separately at NLM, with the following exceptions:

  • Monographic series selected for MEDLINE® are cataloged as serials.
  • Monographic series already cataloged as serials according to past practice generally continue to receive serial treatment (see 5. "Changes in Series Treatment" for additional guidance about changes in series decision).
  • Obvious periodicals (such as journals and newsletters) generally receive serial treatment, including those consisting of analyzable "theme" issues.
  • Titles available only be subscription may receive serial treatment.

When there is doubt about whether to treat a monographic series as classed together or separately, NLM classes it separately.

Until May 1999, NLM provided serial treatment for most numbered monographic series.

4.2. Treatment of Other Types of Numbered Publications

4.2.1. Editions

NLM generally provides serial treatment to directories, bibliographies on a single subject, and handbooks which are issued in numbered editions. The edition numbering is treated as the numeric designator. Monographic cataloging of earlier editions is converted to serial cataloging when periodicity is five years or less and evidence (e.g., three consecutive editions are issued with consistent title, a CONSER record exists, or there is a stated intent of the publisher) is sufficient to indicate that the title meets the definition of a serial.

Textbooks issued in frequently revised editions are not treated as serials.

4.2.2. Publication of Numbered Meetings

Publications of numbered meetings (i.e., conference publications) generally are cataloged separately at NLM.

Publications of numbered meetings may be cataloged as serials when the name of the meeting and the title of the publication remain constant for three consecutive issues.

Conference publications, previously cataloged as separate monographs, are converted to serial treatment, after the third issue is received, if the above criteria are met.

Once the publications of a conference have been accorded serial treatment, earlier or later titles may or may not be given serial treatment on a case by case basis.

4.3. Serials within Serials

A serial, including a monographic series, may be part of another serial or may contain another serial within it. Separate records may or may not be desired for the parent serial, for any serial or series issued with it, or for both.

An analytic of a series may itself be a serial. NLM treats such subseries as follows:

  1. When the parent series is cataloged as a serial at NLM, the subseries is cataloged with the main serial and the subseries title is treated as an added title entry on that main serial bibliographic record.
  2. When the parent series is not treated as a serial at NLM, but the subseries meets the definition of a serial, the subseries is treated as a serial and a serial bibliographic record is created.

A serial may have separately published sections or supplements. If these fit the definition of a serial, they may receive separate records.

One serial may be issued with another as a physical part of it. Generally, a separate record would not be made for a serial which is issued as part of another, except of unusual cases (such as a title in MEDLINE).

4.4. Loose-leaf Publications

If loose-leaf updates consist of replacement pages issued periodically, the work is treated as an integrating resource at NLM. A loose-leaf publication may receive serial treatment if the entire item is replaced periodically and if it otherwise meets the definition of a serial.

5. Changes in Series Treatment

  • As stated in 4.1 "Numbered Monographic Series", monographic series already cataloged as serials at NLM generally continue to receive serial treatment. Should the monographic series title change or the series become unnumbered, however, NLM generally classes the new title separately.
  • Once a decision has been made to class a monographic series separately, the decision generally is not reconsidered, even if receipt of later volumes brings new information (e.g., an unnumbered series becomes numbered retrospectively).
  • Exceptions: NLM converts from monographic to serial treatment when a monographic series becomes an unanalyzable serial or when a title is selected for MEDLINE.

6. Recataloging Policy

  • If the library has already cataloged five or fewer volumes in the series when a classed separately series is converted to a serial, the previously cataloged items are recataloged and relabeled as serial analytics.
  • If the library has already cataloged more than five consecutive volumes in the series, the records will remain as is, and a note is added to both the bibliographic record and the series decision record explaining that earlier volumes are classed separately (e.g., v. 1-6 classed separately).
  • If the library has already cataloged more than five volumes, classing them separately, but the numbering of the five volumes is not consecutive, or the library does not hold the first volume of the series, a decision to recatalog is made on a case by case basis.

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