The American Library Association Glossary of Library and Information Science (1983) defines journal as "a periodical, especially one containing scholarly articles and /or disseminating current information on research and development in a particular subject field."
The Library's first priority is collecting scientific or scholarly journals containing signed papers that report original research. The intent is to assemble a comprehensive collection of the world's most significant research journals in all subjects collected at NLM, from all countries and in any language.
NLM also collects clinical and other practice journals. Collecting emphasis is on those of interest to U.S. health professionals; but NLM also collects works from other countries that document diverse approaches to clinical practice, or that cover health issues unique to a particular region.
Review journals, which summarize and sometimes analyze recent research in a field, have become an important means of biomedical communication. The Library collects substantive review journals likely to be of interest to U.S. health professionals and scholars. NLM collects "current awareness" periodicals -- which provide only cursory summaries -- more selectively, emphasizing those that contain unique subject or geographic coverage or are of particular interest to U.S. health professionals. NLM generally does not collect review journals or current awareness periodicals intended primarily for local or regional audiences, or those that essentially duplicate journal literature already in the collection.
A journal should demonstrate quality of editorial work, including features that contribute to the objectivity, credibility, and quality of its content. These features may include information about the methods of selecting articles, especially on the explicit process of external peer review, statements indicating adherence to ethical guidelines and evidence that authors have disclosed financial conflicts of interest. Commercial sponsorship should not raise questions about the objectivity of the published material. Additional factors that are considered include the publisher and/or sponsoring organization's history and corporate structure, longevity, and record of performance regarding such issues as: quality of publications; experience in scholarly publishing; involvement with the scientific community; disclosure of and adherence to print and online publication standards; and promotion of editorial integrity and independence.
When selecting scholarly and scientific journals, NLM expects, as a benchmark, at least 20% of the articles to be "in scope" - i.e., to fall within the subject collection parameters outlined in this manual. Other periodicals -- those that are not sources of original research -- must be primarily biomedical in content to be considered for selection. The Library may make exceptions to this rule to ensure that the collection provides sufficient geographic heterogeneity. For example, NLM may select basic science or social science journals from developing countries
, which often have little or no medical publishing per se.