The need for fully-effective federated analytics of data sources for clinical trials.
8 affiliations
- 1UCL Innovative Clinical Trials Unit, Institute of Clinical Trials and Methodology, UCL, London, WC1V 6LJ, UK; ORCID: 0000-0001-5957-7275.
- 2UCL Innovative Clinical Trials Unit, Institute of Clinical Trials and Methodology, UCL, London, WC1V 6LJ, UK; ORCID: 0000-0002-6695-5390.
- 3UCL Innovative Clinical Trials Unit, Institute of Clinical Trials and Methodology, UCL, London, WC1V 6LJ, UK; ORCID: 0000-0002-2512-2296.
- 4UCL Innovative Clinical Trials Unit, Institute of Clinical Trials and Methodology, UCL, London, WC1V 6LJ, UK; ORCID: 0000-0002-6718-7661.
- 5Kent, Medway and Sussex Secure Data Environment, Kent, Medway and Sussex Secure Data Environment - NHS England Digital;ORCID: 0009-0004-1807-3758.
- 6School of Medicine, NIHR Nottingham Biomedical Research Centre, University of Nottingham, NG7 2UH, UK; ORCID: 0000-0002-3012-6646.
- 7UCL Innovative Clinical Trials Unit, Institute of Clinical Trials and Methodology, UCL, London, WC1V 6LJ, UK; Transforming Data for Trials programme, Health Data Research UK (HDR UK), London, NW1 2BE, UK; ORCID: 0000-0001-6418-0854.
- 8UCL Innovative Clinical Trials Unit, Institute of Clinical Trials and Methodology, UCL, London, WC1V 6LJ, UK; Data for R&D, "Data Access & Partnerships, Technology Data & Digital", NHS England, London, SE1 8UG, UK; ORCID: 0000-0002-9323-1371.
Abstract
Introduction
Clinical trials are usually analysed in a single environment allowing for flexible analysis including adjustment or stratification by subgroup: 'one-stage' analysis of individual-level data. Health systems datasets, often distributed across geography and providers, can streamline clinical trials. Data are increasingly accessible in secure data environments (SDEs). Future trial analyses may involve working across multiple SDEs. Row-level data and identifiable data often cannot leave, requiring a 'two-stage approach', where summary data from each SDE are meta-analysed.Objective
To quantify the potential loss of precision and concomitant increases in required sample sizes, and to make recommendations for trial design and conduct, if clinical trial data are split across silos (e.g. SDEs).Methods
Simulations used data from clinical trials in breast cancer, tuberculosis and prostate cancer with time-to-event, binary and continuous outcome measures. Silos were mimicked by 1000 random partitions into 2, 4, 10 and 25 equal silos and 4 unequal silos proportionate to the UK nations. Data were analysed as if the data could be pooled ignoring silo, pooled accounting for silo (one-stage) or not pooled (two-stage). Estimates and standard errors were presented graphically.Results
For all three outcome measure types, standard errors increased while point estimates spread out as more silos were introduced. Small biases occurred for binary and time-to-event outcomes. This did not always appreciably reduce efficiency. However, in one example with time-to-event data and the largest number of silos, a near-doubling of sample size would have been required to pre-emptively offset the loss of efficiency.Conclusion
Any need to use a two-stage analysis approach has a negative effect compared to doing a one-stage analysis. Technical and data governance solutions to support one-stage analyses are recommended.
Related
- Multivariate Analysis of Data From Crossover Clinical Trials
- Sample size determination for randomized decentralized clinical trials with longitudinal outcomes
- A Multi‐Task Learning Approach for Identifying Prognostic Variables Across Multiple Historical Clinical Trials
- Automated, Efficient, and Model-Free Inference for Randomized Clinical Trials via Data-Driven Covariate Adjustment
- Valid Data‐Driven Subgroup Selection With Uniform Guarantees in Clinical Trials
BibTeX
@article{fabiane2026need,
title = {{The need for fully-effective federated analytics of data sources for clinical trials.}},
author = {Stella Maris Fabiane and Sharon B Love and David Fisher and Ian R White and Jayne F Tierney and Catherine Dampney and Folkert W Asselbergs and Philip R Quinlan and Macey L Murray and Matthew R Sydes},
journal = {International journal of population data science},
year = {2026},
month = aug,
doi = {10.23889/ijpds.v11i1.3201},
url = {https://europepmc.org/article/MED/42899104},
note = {CC BY},
}
RIS
TY - JOUR
TI - The need for fully-effective federated analytics of data sources for clinical trials.
AU - Stella Maris Fabiane
AU - Sharon B Love
AU - David Fisher
AU - Ian R White
AU - Jayne F Tierney
AU - Catherine Dampney
AU - Folkert W Asselbergs
AU - Philip R Quinlan
AU - Macey L Murray
AU - Matthew R Sydes
PY - 2026
DA - 2026/08/27
JO - International journal of population data science
DO - 10.23889/ijpds.v11i1.3201
UR - https://europepmc.org/article/MED/42899104
AB - Introduction Clinical trials are usually analysed in a single environment allowing for flexible analysis including adjustment or stratification by subgroup: 'one-stage' analysis of individual-level data. Health systems datasets, often distributed across geography and providers, can streamline clinical trials. Data are increasingly accessible in secure data environments (SDEs). Future trial analyses may involve working across multiple SDEs. Row-level data and identifiable data often cannot leave, requiring a 'two-stage approach', where summary data from each SDE are meta-analysed.Objective To quantify the potential loss of precision and concomitant increases in required sample sizes, and to make recommendations for trial design and conduct, if clinical trial data are split across silos (e.g. SDEs).Methods Simulations used data from clinical trials in breast cancer, tuberculosis and prostate cancer with time-to-event, binary and continuous outcome measures. Silos were mimicked by 1000 random partitions into 2, 4, 10 and 25 equal silos and 4 unequal silos proportionate to the UK nations. Data were analysed as if the data could be pooled ignoring silo, pooled accounting for silo (one-stage) or not pooled (two-stage). Estimates and standard errors were presented graphically.Results For all three outcome measure types, standard errors increased while point estimates spread out as more silos were introduced. Small biases occurred for binary and time-to-event outcomes. This did not always appreciably reduce efficiency. However, in one example with time-to-event data and the largest number of silos, a near-doubling of sample size would have been required to pre-emptively offset the loss of efficiency.Conclusion Any need to use a two-stage analysis approach has a negative effect compared to doing a one-stage analysis. Technical and data governance solutions to support one-stage analyses are recommended.
SN - 2399-4908
ER -