Consider an illustrative situation. A site coordinator notices that a participant’s wearable has stopped sending data. The coordinator contacts the contract research organization (CRO). The CRO suggests contacting the device manufacturer. The manufacturer asks for details the site does not have. A week passes before anyone resolves it.
Nobody in that chain acted unreasonably. Each party was working within its own scope. The problem sat in the space between them.
Wearable sensors add a workstream that most trial structures were not built to own.
Why Does Wearable Data Fall Between Parties?
A traditional trial has well-understood roles. The sponsor owns the program. The CRO manages sites, monitoring and trial operations. Vendors supply specific services.
A wearable changes that. It generates data every day, outside the site, through technology the CRO does not make and the manufacturer does not always deploy in trials. Device selection, measure development, logistics, compliance monitoring and data processing all need an owner. When the contract does not name one, the work tends to default to whoever notices a problem first. The same gaps can appear in decentralized clinical trials that use wearable sensor data, where more of the data collection happens away from sites.
What Is the Sponsor Responsible For?
The sponsor owns the scientific question and the decisions that follow from it. That includes:
- The concept of interest the trial needs to measure
- The role a digital measure will play in the trial
- Regulatory strategy and interactions with regulators
- Final decisions on protocol, endpoints and analysis
- Selection of digital endpoint partners and the scope each one covers
The sponsor cannot hand off accountability for the program. It can hand off specific work to partners who are set up to do it. The International Council for Harmonisation (ICH) E6(R3) Good Clinical Practice guidance, which the U.S. Food and Drug Administration (FDA) issued as final guidance in September 2025, says a sponsor may transfer trial-related activities to a service provider, while ultimate responsibility, including for the reliability of the trial data, resides with the sponsor. Transferred activities should be documented in an agreement.
What Is the Primary CRO Responsible For?
The primary CRO typically manages trial operations across sites. That includes site selection and management, clinical monitoring, trial master file management, much of the data management for the overall study, and coordination with the sponsor.
Most CROs are not built around sensor measurement science. Selecting a wearable sensor for a specific patient population, developing algorithms and monitoring continuous sensor data are specialized work that may sit outside a CRO’s standard scope.
What Is the Device Manufacturer Responsible For?
The device manufacturer owns the hardware and its supporting software. That usually includes device performance, firmware, the manufacturer’s own data platform and technical support for the device.
A manufacturer’s role is generally not to decide which measures a trial should use, to train sites on a specific protocol or to monitor whether participants are following it.
What Is a Wearable Sensor CRO Responsible For?
A wearable sensor CRO is a contract research organization that specializes in the selection, deployment, validation, analysis, and interpretation of wearable sensor technologies and digital measures in clinical research.
Rather than replacing a traditional CRO, a wearable sensor CRO often works alongside existing trial partners. It takes responsibility for the digital measurement workstream end-to-end: from measure strategy through the data packages the study team uses.
Responsibility Table: The Digital Measurement Workstream
Every trial is different, and the contract should state who owns each step.
| Workstream step | Sponsor | Primary CRO | Device manufacturer | Wearable sensor CRO |
|---|---|---|---|---|
| Concept of interest and measure strategy | Decides | Consulted | Not involved | Advises |
| Device selection for the population | Approves | Consulted | Supplies device information | Recommends |
| Measure selection | Approves | Consulted | Not involved | Recommends |
| Device shipping to sites | Informed | Coordinates with sites | Supplies devices | Manages |
| Site training on devices | Informed | Coordinates schedules | Provides device documentation | Delivers |
| Wear compliance monitoring | Informed | Informed of site issues | Not involved | Monitors in real time |
| Data ingestion and cleaning | Informed | Integrates with study data | Provides data access | Manages |
| Algorithms and analysis of sensor data | Approves plan | Consulted | Provides device algorithm information | Performs |
| Data packages for the study team | Receives | Receives | Not involved | Delivers |
| Site management and clinical monitoring | Oversees | Manages | Not involved | Not involved |
| Overall trial management | Oversees | Manages | Not involved | Not involved |
Where Does Each Party’s Scope Stop?
Each party’s scope usually stops at the edge of its own discipline, and gaps form where those edges do not meet.
Where a Traditional CRO’s Scope Usually Stops
At the science and operations of the sensor itself: choosing a device for a population, deriving measures and building their validation evidence, running compliance monitoring on continuous data and processing sensor output.
Where a Device Manufacturer’s Scope Usually Stops
At the device. Manufacturers support their hardware and software. They do not typically own protocol-specific training, participant compliance or the design of trial measures.
Where a Wearable Sensor CRO’s Scope Stops
At the rest of the trial. A wearable sensor CRO does not manage sites, provide clinical monitoring or run the overall trial.
How the Work Maps to Trial Stages
In a case study published in July 2025 and presented at the 2025 Digital Biomarkers Summit, VivoSense describes its work with argenx across three trial stages:
- Study Startup: Strategy development, measure selection, and protocol design.
- Study Conduct: Operationalization, monitoring, and data collection.
- Study Closeout: Statistical analysis and clinical validation.
Read the argenx wearable sensor CRO partnership case study.
Questions to Settle Before the Contract Is Signed
- Who selects the device, and on what evidence for this population?
- Who defines the measures derived from sensor data?
- Who ships devices, handles replacements and trains sites?
- Who monitors wear compliance, how often, and who contacts sites when data stops?
- Who ingests, cleans and processes sensor data?
- Who owns the algorithms and the analysis plan for digital measures?
- Who produces the data packages the study team will use, and in what format?
- How do the sensor data and the main study data come together?
- What happens if device software or firmware changes mid-study?
If a question does not have a named owner in the contract, it is likely to become a gap during the study.
For trials with decentralized elements, FDA’s September 2024 final guidance on conducting clinical trials with decentralized elements recommends that the data management plan cover data origin and data flow from all sources to the sponsor. FDA’s December 2023 final guidance on digital health technologies (DHTs) for remote data acquisition recommends that sponsors plan for unanticipated changes to DHTs and keep a record of the timing and nature of any updates for each DHT.
Common Mistakes
Assuming the CRO Covers the Wearable
Site management and sensor measurement science are different disciplines. Check the scope in writing.
Treating the Device Manufacturer as the Study Partner
Manufacturers support their devices. Protocol-specific operations usually sit elsewhere.
Bringing in Specialist Support After the Protocol Is Written
By then, many decisions about devices and measures are already made.
Leaving Compliance Monitoring Unassigned
If nobody is named, the data may go unwatched until analysis, and a healthy wear time figure can hide valid data days a trial cannot use.
How VivoSense Works Alongside Your CRO
VivoSense is a wearable sensor CRO founded in 2010. It works alongside the sponsor’s trial team and CRO on the digital measurement workstream.
VivoSense helps sponsors choose the right device based on the disease state and the population of the patients and choose what measures to capture. It ships devices, trains sites and monitors devices getting to site, getting onto patients and real-time wear compliance through a purpose-built cloud platform. It then ingests data from multiple sensors and devices, cleans it, runs it through its algorithms and delivers formatted regulatory-ready data packages for the study team.
Frequently Asked Questions
What is a wearable sensor CRO?
A contract research organization that specializes in the selection, deployment, validation, analysis, and interpretation of wearable sensor technologies and digital measures in clinical research.
Does a wearable sensor CRO replace a traditional CRO?
No. A wearable sensor CRO often works alongside existing trial partners and covers the digital measurement workstream.
Who is responsible for wear compliance in a clinical trial?
It depends on the contract. Without a named owner, it can fall between the CRO and the device manufacturer. Where a wearable sensor CRO is engaged, it typically monitors it.
Does the device manufacturer manage wearable data in a trial?
Manufacturers usually support the device and its software. Protocol-specific data monitoring and processing is typically handled by another party.
What does VivoSense do for clinical trials?
VivoSense works alongside the sponsor and CRO on the digital measurement workstream, from device and measure selection through site training, real-time wear compliance monitoring and delivery of data packages for the study team.
Let’s Talk
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