Research literacy · source systems
Research databases: what PubMed, trial registries, and regulator databases each can tell you
A database is a record system with a purpose. Use the right record type for the question, then keep its limitations visible.
PubMed locates literature records
PubMed is maintained by the U.S. National Library of Medicine and helps readers locate biomedical citations, abstracts, linked full text, publication types, and related articles. It is useful when the question is whether a paper exists and what that paper reports.
A PubMed record does not by itself establish authorization, current availability, product quality, or a completed clinical conclusion. Readers still need to inspect the original source, the study design, and whether later evidence changes the context.
ClinicalTrials.gov describes study records
ClinicalTrials.gov organizes registration information such as study type, recruitment status, eligibility, outcomes, dates, and results where they have been posted. It is useful for seeing what a protocol planned to investigate and whether a record is recruiting, completed, or otherwise updated.
A record’s status is not a substitute for a publication or outcome. The most responsible use is to identify the study, read the listed endpoints, and then look for posted results or linked papers rather than assuming registration means success.
Regulator databases answer jurisdiction-specific questions
Official regulatory resources can describe authorizations, safety communications, recalls, monographs, or database entries in a particular country. Those records are different from journal publications because they address a regulatory question rather than the entire scientific literature.
This guide does not interpret database results as medical, legal, or product advice. It gives readers a simple routing rule: literature for published research, registries for study records, and official regulators for jurisdiction-specific status and safety notices.
Search fields are retrieval tools, not evidence rankings
Databases make different information searchable: title words, author names, identifiers, publication types, registry fields, subject headings, dates, and linked records. A high search ranking can reflect the words entered, recent indexing, or database relevance rules. It does not tell a reader that a result is more reliable than every item lower on the page, or that the record answers the claim they are checking.
Use the database to locate and classify documents, then inspect the record itself. The useful habit is to save the identifier or stable URL, check the source date and document type, and look for linked corrections or related publications. This reduces the risk that a changing search screen becomes the only evidence trail for a claim.