Privacy and Security
28% of trials report in ClinicalTrials.gov plans to share individual participant data (IPD) for data re-use
The clinical trials environment supports responsible re-use of data.
This metric assesses the extent the clinical trials environment supports responsible re-use of data. One way to measure this is quantifying how sponsors report the prevalence of consent forms presented to trial participants that discuss potential use of data for future research. This preliminary finding indicates over a quarter or 28% of trials report in ClinicalTrials.gov plans to share individual participant data (IPD) for data re-use in a cross-sectional analysis of trials begun since 2023. This may be interpreted as a modest commitment to data sharing across the clinical trials enterprise with room for improvement for making IPD data sharing a routine expectation in the design and conduct of interventional trials in the U.S.
Findings
A cross sectional characterization of the current clinical trials enterprise (for trials started in 2023, n=7,673) shows 28% of interventional studies with at least one U.S. site reported plans to share IPD data in ClinicalTrials.gov ("Yes", 28.0%; "No", 66.1%; "Undecided", 5.9%).
Among these trials, 45% of NIH-funded trials reported plans to share IPD data ("Yes", 44.7%; "No", 50.5%; "Undecided", 4.8%) compared to 29% of industry-funded trials ("Yes," 29.4%; "No", 64.3%; "Undecided", 6.3%).
In a follow-up cross sectional analysis of interventional trials with at least one U.S. site initiated in 2018 (5 years prior), 17% of trials reported plans to share IPD data ("Yes", 16.6%; "No", 70.9%; "Undecided", 12.6%) representing a roughly 10% increase in data sharing plans across a 5 year span among all U.S. interventional trials.
Further exploration of metric
To be added.
Limitations
ClinicalTrials.gov does not include all U.S. clinical trials. Although all “applicable clinical trials” and NIH-funded interventional studies must be registered, and public registration is encouraged, select trials may be absent from ClinicalTrials.gov. Policies enacted since 2012, such as the NIH Policy on the Dissemination of NIH-Funded Clinical Trial Information, have increased the scope of trials required to be registered in ClinicalTrials.gov and improved reporting requirements.
Methodology
This preliminary metric result comes from "Characteristics of Interventional Clinical Trials Registered in ClinicalTrials.gov, 2018-2023" (Sullenger, et al.) recently reported to the NIH Pragmatic Trials Collaboratory Grand Rounds (July 18 2025).
Authors used the database for Aggregate Analysis of ClinicalTrials.gov (AACT) to conduct retrospective analyses of clinical research studies registered in ClinicalTrials.gov. They extracted all 493,116 clinical studies registered in ClinicalTrials.gov as of 05/01/2024. Cross-sectional analysis was limited to interventional trials started in 2023 with at least one U.S. site. Analysis was restricted to trials with at least one U.S. site, defined as a U.S.-based facility with the ability to enroll trial participants because such trials are more likely to comply with U.S. policies and laws and fully report required information in ClinicalTrials.gov. The same methodology was used to identify interventional studies started in 2018 for the five-year longitudinal cohort. Authors also evaluated the subgroup of phase 3 interventional trials started in 2018. All withdrawn studies, those halted prior to enrollment of the first participant, were excluded.
Both cohorts were characterized by funding source, based on lead sponsor and collaborator information [industry, NIH, other U.S. federal agencies, other (i.e., individuals, universities, community-based organizations, foundations)]; categorical and median (25th–75th percentile) enrollment; completion status; therapeutic area (cancer, cardiovascular, mental health); intervention type; study phase (for studies including a FDA regulated drug/biologic); interventional model; number of study sites; site location(s); and plan to share individual participant data. Authors also conducted a subgroup analysis of phase 3 trials started in 2018 that studied a U.S. FDA-regulated drug or biological product.
Authors present categorical characteristics as frequencies and percentages and continuous characteristics as medians and 25th-75th percentiles. Summaries were generated using available data. Missing values were excluded. SAS version 9.4 was used for all statistical analyses.