The Adherence Imperative: Clinical Operations and Patient Centricity

Contributed Commentary by Ashmee Bharadia, Vice President, Patient Recruitment & Retention, ICON

September 11, 2026 | Participant adherence is a leading indicator of trial health. Adherence reflects patient centricity as a measure of how effectively a clinical trial has removed barriers, supported participants throughout the study journey and enabled sites to deliver a high-quality participant experience. As participant experiences improve, usually so does adherence, especially considering that approximately half of all dropouts in phases 2-3 come down to participant choice rather than adverse reactions or study staff decisions.

High retention supports data completeness, protocol adherence, and timeline predictability, while reducing the operational and financial costs related to participant replacement. As protocols become more complex, retaining participants through study completion is increasingly important to generating robust evidence and delivering successful trial outcomes.

Adherence improves with practical participant-focused support, but it also improves with site support. An integrated support model creates conditions for successful participation, long-term retention, improved data quality, and study performance while creating a better experience for all stakeholders.

Complexity Creates Compounding Adherence Challenges

Clinical trials are more complex, with protocols that now require more procedures, assessments, and data collection activities than in the past. These requirements place greater demands on both participants and sites.

Recent Tufts CSDD analyses found that between 2016 and 2021, phase 3 trials experienced a 37% increase in mean endpoints and a 42% increase in the total number of procedures. More than 40% of procedures now support secondary, tertiary, and exploratory endpoints rather than core study objectives, adding further burden to participation. And the procedures themselves are taking longer.

For participants, the increasing procedure and visit demands can translate into technology requirements, time, and travel commitments that compete with personal responsibilities. Over time, even seemingly minor inconveniences can erode engagement and increase the risk of missed visits, incomplete assessments, or withdrawal from the study.

Sites face the same pressures while also managing staffing constraints, administrative workloads, technology onboarding, and increasingly complex study operations. As site burden increases, many are declining to participate in further research opportunities. For those that accept, the execution burden decreases the time available for participant education, communication, and follow-up, and the quality of those interactions may suffer.

Adherence challenges frequently emerge where participant and site burdens intersect. Improving retention therefore requires more than motivating participants. It requires reducing friction across the study ecosystem and ensuring that both participants and sites receive the support needed to navigate growing trial complexity successfully.

Anticipating Dropout Risks: Working closely with sites to gather patient feedback through surveys and focus groups helps sponsors better understand and prepare for the specific burdens participants may experience. These challenges vary across disease areas, socioeconomic status, geographies, and individual participant personas. However, common high-impact elements include:

Travel and logistics: Coordinating transportation, accommodation, and reimbursement reduces the burden of attending study visits and helps minimise missed appointments.

Technology: Dedicated onboarding, training, and technical assistance help participants successfully use ePRO platforms, wearables, and remote monitoring tools.

Flexible participation models: Hybrid and decentralised approaches, including in-home visits and remote assessments, can make participation more convenient and sustainable. In one fully in-home orphan drug study conducted in North America, participant retention reached 97%.

Personalised engagement: Patient support services, appointment reminders, and proactive outreach help participants stay connected, informed, and engaged throughout the study.

The Operational Hinge: Site Support

While patient support services help remove barriers to participation, sites remain the centre of the participant experience. Their capacity, resources, and engagement often determine how effectively participants are recruited, supported, and retained throughout a study.

Staffing shortages, administrative demands and operational complexity can divert attention away from participant-facing activities. Closing resource gaps through clinical research nurses, clinical research coordinators, clinical trial managers, and site managers helps maintain continuity and participant support. For example, a massive vaccine study included a dedicated site resourcing service model. Sites that availed of the resourcing service had better retention: 2-4% dropout rates compared to 6-10% for those without resourcing.

Reducing administrative burden can have a similar effect. Activities such as document management, scheduling, training coordination, and data entry consume significant time. When these tasks are streamlined, site teams can devote more attention to participant education, communication, and adherence support.

Operational support also helps sites execute studies more efficiently. Protocol-specific training, secure document exchange, and visit-by-visit guidance reduces friction and enables consistent study delivery. Tailored support, including scientific training, recruitment planning, and ongoing peer-to-peer engagement, can further strengthen site performance and motivation throughout trial execution.

In one pediatric migraine study where we paired direct-to-patient engagement with formalised site support, patient retention and compliance hit 92%. Ultimately, every hour removed from administrative burden can be reinvested in participant engagement.

Integrate the Support System

Executing an integrated participant recruitment and retention strategy requires a support system that anticipates challenges, reduces burden, and enables timely intervention throughout study stages.

Alignment and planning: Discovery sessions with sites can help identify operational risks, participant burden, and resource requirements before recruitment begins. Aligning expectations from the outset and incorporating data-driven site selection and over-selection strategies can also reduce the impact of site attrition and recruitment delays.

Connected technology infrastructure: Providing sites with streamlined systems for training, documentation, communication, and engagement reduces administrative burden and creates more consistency. Integrated tech platforms can create smoother, more intuitive workflows for site staff while also creating predictability and improved forecasting. Connected data systems enable earlier insights that would allow sponsors or CROs to course-correct before small patterns become big problems and participant engagement declines.

Dedicated expertise: Dedicating site liaisons can strengthen relationships with investigative teams and help identify risks early, while embedded clinical research personnel can provide ongoing operational expertise to support quality, recruitment and retention. When site staff are empowered, they are better positioned to build the trust, responsiveness and continuity that encourage participants to remain in a trial through completion.

Getting More Than Satisfaction: Patient centricity should be measured through operational outcomes, as well as participant perception. The strongest measurements connect the support interventions to the behaviours that underpin adherence and retention.

For example, travel support may help reduce missed visits, technology assistance can improve ePRO completion, and personalized engagement programs may encourage participants to stay connected throughout longer studies. Likewise, reducing administrative burden on sites enables coordinators and investigators to spend more time on participant communication, education and follow-up.

Sponsors should therefore evaluate whether support models are influencing key indicators such as:

Visit completion rates
Participant retention rates
ePRO completion and compliance
Missed assessments
Protocol deviations
Site satisfaction
Participant satisfaction

Viewed together, these metrics provide a more complete picture of study health.

Ethical and Operational Imperative

The most successful studies recognize that patient and site centricity are not separate strategies but complementary elements of the same operational model. Participants rely on sites for education, guidance, and support throughout the trial journey, while sites depend on sponsors and CROs for the resources, infrastructure, and partnership needed to deliver a positive participant experience. Industry studies consistently illustrate this relationship with data that shows that sites with positive sponsor and CRO relationships enrol more participants, meet enrolment targets faster, and retain participants longer.

As study complexity continues to increase, improving retention requires a broader view of adherence. Clinical development stakeholders have a responsibility to minimise unnecessary burden and create conditions that support continued participation. And operationally, retention is essential to data quality, study timelines, and overall study outcomes.

Success depends on supporting both participants and the sites that care for them. In doing so, sponsors can create a more resilient clinical trial ecosystem that reduces burden, strengthens adherence, and delivers better outcomes for patients, sites, and sponsors alike.

Ashmee Bharadia is vice president for ICON Patient Recruitment and Retention. She joined ICON in 2011, working with the largest strategic account in various project management roles and as a clinical program manager for cardiovascular. Ashmee started her career in progressive roles from CRA to project management across Sanofi Aventis, Schering Plough, Novartis and Amgen covering respiratory, immunology, infectious, dermatology and neurology. In 2016, Ashmee held a leadership position with a small CRO focused on developing the project management group and gained experience working with innovative start up and biotech companies. Ashmee also established a new group focused on strategic business optimization, technology implementation, and global process improvements working with the corporate and operational leadership. Ashmee holds qualifications in Lean Six Sigma and Change Management, and a bachelor's degree with honors in pharmaceutical chemistry from Queen Mary, University of London. She can be reached at ashmee.bharadia@iconplc.com.