AI for Evidence Utilization · Retrieve
PubTator 3.0: an AI-powered literature resource for unlocking biomedical knowledge
Chih-Hsuan Wei†, Alexis Allot†, Po-Ting Lai, Robert Leaman, Shubo Tian, Ling Luo, Qiao Jin, Zhizheng Wang, Qingyu Chen, Zhiyong Lu
† Joint first authors
Nucleic Acids Research 2024
These slides were generated with the help of AI and may contain errors.
01Motivation
Keyword matching can miss relevant biomedical evidence
- Different names for the same biomedical concept can reduce recall in keyword searches.
- Articles can mention both query entities without evidence for the requested relationship.
| Entities | Map synonymous names to a shared biomedical identifier. |
| Relations | Specify a relationship (e.g., a chemical reducing gene expression). |
Source: Introduction, pp. W540–W541.
02Method
PubTator enables entity and relation search
- PubTator resolves synonymous entity names and retrieves articles with evidence for specific relationships.

03Method
PubTator annotates new biomedical articles weekly
- AIONER identifies 6 entity types; normalization maps entity mentions to database identifiers.
- BioREx extracts 12 relation types for 8 entity-type pairs.

04Resource
PubTator provides large-scale biomedical annotations
- PubTator searches PubMed abstracts and full-text articles in the PMC Open Access Subset.
- The web interface enables interactive search; APIs and bulk downloads enable programmatic use.
~36M
PubMed abstracts
6M+
PMC-OA full texts
1.6B+
entity annotations
33M
relation annotations
Counts in the 2024 paper. Abstract and full-text collections overlap; annotation counts include repeated mentions and relations. Source: System overview, p. W541.
05Result
PubTator achieves 90.0% pooled precision in 12 retrieval case studies
- 2 curators evaluated the top results for evidence of a relationship between the query entities.
- PubTator achieves higher pooled precision than PubMed and Google Scholar in this evaluation.
| Search system | Relevant / judged | Pooled precision |
|---|---|---|
| PubTator 3.0 | 216 / 240 | 90.0% |
| PubMed | 84 / 103 | 81.6% |
| Google Scholar | 98 / 202 | 48.5% |
Up to 20 results per query; denominators vary by system. Searches used 12 selected entity pairs on 19 May 2023. Curators knew the search system. Source: Case study I, pp. W543–W544.
06Case Study
PubTator improves GPT-4 citation accuracy on 8 questions
- GPT-4 uses 3 PubTator APIs to retrieve evidence for biomedical relationships.
- In a qualitative evaluation of 8 questions, PubTator-augmented GPT-4 achieves higher citation accuracy than PubMed-augmented and standard GPT-4.
| Find the entity | Resolve a concept (e.g., breast cancer) to a standardized identifier. |
| Find relations | Identify entities with the requested relation (e.g., drugs that treat breast cancer). |
| Find evidence | Retrieve PubMed article identifiers for evidence of the requested relationships. |
Citation accuracy measures if cited articles provide evidence for the stated relationships. Source: Case study II, p. W544.
07Limitations
The 2024 PubTator system extracts relations from abstracts
- In the 2024 system, relation extraction uses abstracts only; entity annotation also includes full texts.
- Relation extraction includes 12 types, and automated annotations can contain errors.
- The case studies evaluate 12 entity-pair queries and 8 questions; broader retrieval and clinical performance require further evaluation.
08Summary
PubTator 3.0 enables entity and relation retrieval
| Background | Biomedical questions often concern relationships between entities. |
| Problem | Keyword matching can miss synonyms and specific relationships. |
| Approach | PubTator uses normalized entities and extracted relations for search. |
| Results | 90.0% pooled precision (216/240) in 12 retrieval case studies. |
| Conclusion | Entity and relation annotations enable biomedical evidence retrieval. |