PaperTrace

What Quick Search searches

The databases behind a Quick Search answer, what each covers and what it does not, stated from how the search runs. As of 8 November 2026.

Where Quick Search looks

As of 8 November 2026. Each answer lists the databases it searched in its Methodology tab.

  • OpenAlex: The main search. Runs by keyword and by meaning, with no field restriction, unless it is left out in Search filters or is unavailable. Returns journal articles and other works; preprints only when Include preprints is on.
  • PubMed: Added for health, medicine, life-science and biology questions, or when chosen in Search filters. Journal articles; preprints only when Include preprints is on.
  • Europe PMC: Added alongside PubMed for the same questions, and used when OpenAlex cannot be reached. Life-science literature, with open-access full text where licensed.
  • Crossref: A fallback, used when OpenAlex cannot be reached or a paper search finds nothing. Journal articles and conference papers; titles and metadata only, no abstracts.
  • Semantic Scholar: A fallback, used when OpenAlex cannot be reached or a paper search finds nothing, and only where a key is configured. Metadata only.
  • arXiv: Added for questions outside health and life science, or when chosen in Search filters. Preprints, labelled as such, with links to their published versions where arXiv records one.
  • ClinicalTrials.gov: The Trial landscape tool searches it by topic. An answer looks up a registered trial by its NCT number, and a trial the question names by its exact acronym; a two-word name such as Look AHEAD, which no acronym lookup can find, is matched through the registry record of a report that carries the trial’s NCT number.

What it covers, content type by content type

  • Journal articles: Searched: OpenAlex (the main search), plus PubMed and Europe PMC for health and life-science questions.
  • Preprints: arXiv is searched for questions outside health and life science, and when it is chosen in Search filters; its preprints are labelled, and an abstract is quoted only under a CC BY or CC0 licence. Other preprints are left out unless Include preprints is on; then they come from the records OpenAlex, Europe PMC and PubMed hold (and Crossref and Semantic Scholar as fallbacks). No other preprint server is searched directly.
  • Conference proceedings and meeting abstracts: No proceedings index is searched in a normal run. Records typed as proceedings are not excluded from OpenAlex, and Crossref asks for proceedings articles when it runs as a fallback. ASCO and AACR meeting abstracts can be searched on their own with the Meetings filter; ESMO and EDCC abstracts are not available.
  • Books and book chapters: Not searched as a source. OpenAlex and Europe PMC do not exclude book records, and text is read only where the licence allows.
  • Theses and dissertations: Not searched as a source. OpenAlex and Europe PMC do not exclude thesis records, and text is read only where the licence allows.
  • Patents: No patent database is searched.
  • Trial registrations: ClinicalTrials.gov only. ISRCTN, the EU registry, ChiCTR, ANZCTR and other registries are not searched.
  • Reports, standards and datasets: Not searched as a source. OpenAlex does not exclude report, standard or dataset records.
  • Records in languages other than English: Searches are written in English. Records in other languages are not excluded, but they are not specifically searched for.

By field

Fields differ in where their work is published. This is what Quick Search does for each.

  • Medicine and life sciences. Searched through OpenAlex, with PubMed and Europe PMC added for health and life-science questions. Relies on preprints (arXiv outside health questions), conference proceedings and meeting abstracts (no proceedings index searched), trial registrations (ClinicalTrials.gov only). A trial the question names is looked up in ClinicalTrials.gov by its NCT number or exact acronym; a two-word name, through the registry record of a report that carries its NCT number. Testing so far has used medical questions, mostly about named clinical trials; answer quality beyond them is not yet established.
  • Climate, environment and ecology. Searched through OpenAlex, with arXiv preprints added; PubMed and Europe PMC are added only for questions about health or life science. Relies on preprints (arXiv outside health questions), reports, standards and datasets (not searched as a source). Answer quality in this field is not yet established: ten test questions are written, and no live answers to them have been reviewed by a person.
  • Engineering, energy and materials. Searched through OpenAlex, with arXiv preprints added; PubMed and Europe PMC are added only for questions about health or life science. Relies on conference proceedings and meeting abstracts (no proceedings index searched), patents (not searched), reports, standards and datasets (not searched as a source), theses and dissertations (not searched as a source). Answer quality in this field is not yet established: ten test questions are written, and no live answers to them have been reviewed by a person.
  • Computing, mathematics and statistics. Searched through OpenAlex, with arXiv preprints added; PubMed and Europe PMC are added only for questions about health or life science. Relies on conference proceedings and meeting abstracts (no proceedings index searched), preprints (arXiv outside health questions). Answer quality in this field is not yet established: ten test questions are written, and no live answers to them have been reviewed by a person.
  • Economics, policy and social sciences. Searched through OpenAlex, with arXiv preprints added; PubMed and Europe PMC are added only for questions about health or life science. Relies on preprints (arXiv outside health questions), books and book chapters (not searched as a source), reports, standards and datasets (not searched as a source). Answer quality in this field is not yet established: ten test questions are written, and no live answers to them have been reviewed by a person.
  • Education, psychology and humanities. Searched through OpenAlex, with arXiv preprints added; PubMed and Europe PMC are added only for questions about health or life science. Relies on books and book chapters (not searched as a source), theses and dissertations (not searched as a source), preprints (arXiv outside health questions). Answer quality in this field is not yet established: ten test questions are written, and no live answers to them have been reviewed by a person.

What this page covers

This describes Quick Search. Review projects and the API have their own source lists.