AI for Evidence Generation · Case Reports
A Large-scale Dataset of Patient Summaries for Retrieval-based Clinical Decision Support
Zhengyun Zhao*, Qiao Jin*, Fangyuan Chen, Tuorui Peng, Sheng Yu
* equal contribution
Scientific Data 2023
These slides were generated with the help of AI and may contain errors.
01Motivation
Case reports are rich evidence machines can’t search
What case reports capture
- They sit near the base of the evidence pyramid.
- Yet they record individual patients, rare diseases, and unusual presentations the higher tiers miss.
Why they’re unusable
- The evidence is scattered, unstructured narrative.
- Making it searchable needs a large, structured, openly licensed collection — which did not exist.
02Method
167k patient summaries, mined at scale
- 167k patient summaries extracted from PubMed Central case reports.
- 3.1M patient–article and 293k patient–patient links, mined from citation signals.

03Method
A repeatable extraction pipeline
- Patient summaries identified from PMC Open Access case reports via extraction triggers.
- Filtered by length, language, and demographics.
- Yields 167k patient-note candidates.

04Benchmark
Two retrieval tasks for decision support
- Patient-to-article (PAR) — find the literature relevant to a patient.
- Patient-to-patient (PPR) — find similar patients.
- Both scored against the mined relevance annotations.

05Result
Large, open — with clear headroom
- An order of magnitude beyond earlier case-report collections.
- Released with a public leaderboard; strong retrievers still leave much signal untapped.
| Retriever | PAR · MRR | PPR · MRR |
|---|---|---|
| BM25 (sparse) | 18.7 | 22.9 |
| MedCPT | 13.1 | 13.7 |
| PubMedBERT | 19.8 | 19.4 |
| BioLinkBERT | 19.1 | 21.2 |
| SPECTER | 17.9 | 15.1 |
| RRF (fusion) | 29.9 | 27.8 |
Retrieval quality (MRR×100) on patient-to-article (PAR) and patient-to-patient (PPR). Source: Table 4.
06Impact
A reference corpus across top-tier medical AI
- Underpins rare-disease AI — a data source for Nature’s DeepRare agent and the basis of The Lancet Digital Health’s RareArena benchmark.
- An evaluation corpus in Nature Communications, npj Digital Medicine & Communications Medicine studies.
- Seeds new benchmarks — our MedCalc-Bench (NeurIPS’24) and CaseReportBench (ACM CHIL’25).
- Released as an open dataset with a public ReCDS retrieval leaderboard.
07Summary
PMC-Patients at a glance
| Background | Millions of published case reports describe real patients and their care. |
| Problem | That case-report evidence is rich but unstructured and unsearchable. |
| Approach | Mined 167k patient summaries + 3.1M patient–article links from PMC. |
| Results | The ReCDS benchmark for patient-to-article & patient-to-patient retrieval. |
| Impact | A reference corpus — from Nature’s DeepRare to our MedCalc-Bench. |