NLM chooses journals for the collection based on the criteria in the Collection Development Guidelines of the National Library of Medicine. Journals that are selected for the NLM collection must have sufficient subject matter within the scope of biomedicine and health-related life sciences and should demonstrate quality of editorial work, including features that contribute to the objectivity, credibility, and quality of its content.

NLM looks for conformance with guidelines and best practices published by professional organizations, including Recommendations for the Conduct, Reporting, Editing, and Publication of Scholarly Work in Medical Journals from ICMJE, Code of Conduct and Best Practices Guidelines from COPE and Principles of Transparency and Best Practice in Scholarly Publishing (joint statement by COPE, DOAJ, WAME, and OASPA).