anamnesis-data/clinical_trials_history_sample

Clinical Trials Version History: Sample

A free sample of the Clinical Trials Version History dataset by Anamnesis Data: structured medical and scientific data for biotech, pharma and healthcare research. Public trial registries show only a trial's latest state. This dataset keeps every version, so you can see what a trial said on any past date, or when a sponsor moved a completion date.

The sample holds 20 complete trials (741 versions), one Parquet file per table (79 tables, 221,561 rows). Every row of every table for these trials is included, so joins work as they do in the full dataset, which covers ~605K trials. The trials were chosen so that every table, including the rarer results and safety tables, has rows.

Example queries

sample_queries.sql holds 12 ready-to-run DuckDB queries, each explained in a comment:

• Basic: the current record of every trial, status changes over time, versions per trial.
• Multi-table: the registry as of a past date, completion-date slips by phase, primary-outcome results, serious adverse event rates, arms and their interventions, sponsor site footprint.

They run against setup.sql, which creates one view per table (see Quick start).

Quick start

Download the repository, then in DuckDB, from that folder:

.read setup.sql          -- one view per table, named after its folder
.read sample_queries.sql -- the example queries above

-- the current record of every trial
SELECT nct_id, nct_version, overall_status, lead_sponsor_name
FROM core
QUALIFY row_number() OVER (PARTITION BY nct_id ORDER BY nct_version DESC) = 1;

Or read a table in place, or with the datasets library:

SELECT * FROM 'hf://datasets/anamnesis-data/clinical_trials_history_sample/core/*.parquet' LIMIT 5;

from datasets import load_dataset
core = load_dataset("anamnesis-data/clinical_trials_history_sample", "core", split="train")

What's inside

Each folder is one table. core has one row per trial version; interventions, conditions, phases, arm_groups, locations and the results_* tables (participant flow, baseline, outcomes, adverse events) hang off it. Tables with nct_version join to core on (nct_id, nct_version); per-trial tables join on nct_id.

Things to know:

• Versions. nct_version is the source's own 0-based version number for a trial.
• No "current" flag. The current record is a trial's highest nct_version, as in the query above. It is the latest version held here, which can trail the live record.
• Obsolete IDs. Every table ends with is_obsolete and obsolete_by, which flag registrations since merged into another. None of the sample's trials is obsolete.
• Raw text. Text is as collected, uncleaned. Many fields contain HTML-escaped characters such as & or '.

Source and license

Trial records come from ClinicalTrials.gov, a U.S. Government database operated by the National Library of Medicine at NIH; no proprietary rights are claimed in them, and the site's terms apply to them. Newest change in this sample: 2026-08-28. We restructured the records into tables and a subset of fields; dates given only as a month or year are set to its first day (a *_precision column, where present, keeps the original). Other values are as returned.

The compilation (structure, schema, version history and documentation) is licensed CC BY-NC 4.0. This sample is public and not gated. For commercial licensing and the full dataset, contact licensing@anamnesisdata.com or visit anamnesisdata.com.

Citation

@misc{clinical_trials_history_sample_2026,
  title  = {Clinical Trials Version History: Sample},
  author = {{Anamnesis Data}},
  year   = {2026},
  url    = {https://huggingface.co/datasets/anamnesis-data/clinical_trials_history_sample}
}