Decentralised clinical trials (DCTs) - the basics
The double-blinded randomised controlled trial has been the gold standard for clinical research since the 1940s. It remains rigorous and well-understood. It is also expensive, slow, and dependent on participants being able and willing to travel to a physical site. Tens of thousands of trials are registered worldwide each year, and the operational costs of running them in this traditional model are significant.
Decentralised clinical trials (DCTs) address this by moving the trial to the participant rather than the participant to the trial. Digital platforms, smartphone apps, and wearable devices make it possible to collect data remotely, removing many of the logistical barriers that have historically limited participation and increased costs. A review of remote data capture, wearables, and digital biomarkers in decentralised trials describes this shift as more than a temporary adaptation: continuous physiological measurement outside a clinic, once a novelty, is becoming a standard research tool precisely because it opens up monitoring possibilities a site visit every few weeks simply cannot match.
The problems DCTs are designed to solve
Scheduling and travel burden. Traditional site-based trials require participants to attend in person, often repeatedly. This creates real barriers: working patterns, caring responsibilities, distance, and transport costs all contribute to dropout. Remote participation through a digital platform removes this entirely for many data collection tasks.
High staff costs. Participant management in a centralised trial requires substantial administrative resource over extended timeframes. Well-designed DCT platforms reduce this overhead by enabling participants to self-serve for routine tasks without requiring staff time for each interaction.
Data quality problems from manual handling. Transcribing paper records introduces errors. DCT platforms that use validated electronic capture reduce these errors at the point of entry rather than catching them later in cleaning and monitoring.
Geographic restriction. A site-based trial can only recruit from the population close enough to attend. DCT models allow geographically diverse recruitment, which produces more representative cohorts and findings that are more generalisable across populations.
Participant burden. Travel, rigid scheduling, and time commitments reduce engagement and can drive dropout. When participation fits into a participant's own routine rather than requiring them to reorganise around site hours, compliance tends to improve.
Traditional versus decentralised, at a glance
Neither model is universally better. The right choice depends on what the study actually needs to measure and from whom.
| Factor | Traditional site-based | Decentralised |
|---|---|---|
| Participant travel | Required for most visits | Minimal to none for many tasks |
| Recruitment pool | Limited by proximity to site | Can span a much wider geography |
| Data entry | Often manual, transcribed later | Captured electronically at source |
| Staff overhead | High, concentrated at sites | Lower, more self-service |
| Best suited to | Procedures requiring in-person equipment or supervision | Outcomes that can be measured remotely and continuously |
The economic argument
Bringing a new therapy to market is a famously expensive undertaking, with independent cost estimates in the billions of dollars once failed candidates and the full development timeline are factored in. A significant proportion of that cost is in clinical trial operations. DCT approaches do not eliminate this cost, but they shift the balance: less spend on site infrastructure and coordination, more capacity for data collection and participant reach. Continuous digital biomarker data, in particular, can capture patterns a monthly clinic visit would simply miss, which changes the cost-benefit calculation for certain kinds of studies even before travel and staffing savings are counted.
That said, the shift isn't without friction. Adoption research canvassing clinical research stakeholders found real, unresolved questions still sitting alongside the enthusiasm: data standardisation across different wearable devices, participant comfort with unfamiliar technology, and regulatory clarity all remain works in progress rather than solved problems. None of this undermines the case for DCTs. It just means the basics are more nuanced than "digital is simply better," and worth understanding before assuming a decentralised design is the automatic upgrade.
Where this is heading
The DCT model accelerated significantly during the COVID-19 pandemic, when site-based research became difficult or impossible for extended periods. What emerged was a more permanent shift in appetite for remote and hybrid approaches that continues to develop as regulatory frameworks catch up.
The direction of travel looks less like a wholesale replacement of the traditional trial and more like an expanding toolkit: some studies suited to fully remote design, many others landing somewhere in a hybrid middle ground, with the balance chosen deliberately rather than defaulted into. Understanding the basics well enough to make that choice, rather than assuming decentralisation is either a silver bullet or a passing trend, is the more useful place to start.