After more than a decade working alongside sponsors, CROs and sites, I’ve seen the same pattern repeat itself. A study launches with optimism. Enrollment projections look good. Sites are eager to get started. Then, the funnel starts leaking patients long before anyone blames retention.

That’s because when we talk about patient retention, we usually focus on the wrong phase of the trial.

Retention is typically framed as a mid-study challenge: missed visits, disengaged participants and dropouts after randomization. Those issues are real, but they’re not where retention is breaking down most often today. According to survey data from hundreds of site staff and clinical researchers in our recently released State of Enrollment 2026 Report, the most frequent patient drop-off occurs before patients are even enrolled: 48% during pre-screening, 38% during phone screening and 36% during eligibility review.

In other words, many of the patients the industry counts as “lost” were never truly retained in the first place.

Retention isn’t failing mid-study, it’s failing at the front door

This data mirrors what I hear from sites every day. Patients express interest, respond to outreach and sometimes even complete an initial form or screeners only to disengage once the reality of the study becomes clear.

No matter the reason, none of this shows up in enrollment dashboards, but it has real consequences.

When patients drop off during pre-screening or eligibility, sites absorb the operational burden. They’re the ones making calls, explaining exclusions, reworking schedules and starting over with the same unrealistic enrollment timelines still hanging over them. Over time, this cycle erodes site capacity and trust, making both enrollment and true retention harder.

From my perspective, this is the industry’s blind spot: we’re investing heavily in downstream retention strategies while ignoring the upstream friction that prevents patients from ever getting to their first visit.

Why this matters more in 2026 than ever before

Enrollment has long been the headline metric for clinical trial success, but heading into 2026, patient retention is becoming the real differentiator.

Data tells us that early patient experience is now a leading indicator of study performance. In other words, if patients are disengaging at pre-screening or screening, it’s a signal that the study may struggle to stay on track.

Top-performing studies are already responding to this shift. They’re asking harder questions earlier: Are we overestimating how many patients will realistically qualify? Are our screening processes aligned with site capacity? Are we setting expectations clearly at first contact or unintentionally discouraging participation?

Retention starts at first touch, not first visit

One of the most important shifts I’ve seen emerging is the recognition that retention begins at the first touch, not the first visit. The moment a patient encounters a study, each and every interaction either builds momentum or introduces friction.

When eligibility criteria exclude more than a third of interested patients, that’s a feasibility challenge. When phone screening becomes a drop-off point, that’s a capacity mismatch. And when pre-screening filters nearly half of potential participants out from the beginning, it’s worth asking whether the trial was designed with real-world patients in mind at all.

If we continue to define retention as keeping enrolled patients engaged we’ll miss the opportunity to fix what’s broken.

Designing trials patients can realistically enter and finish

The takeaway isn’t that retention strategies don’t matter. It’s that most of them start too late.

As an industry, we need to treat early-stage patient drop-off as a design signal, not a failure to be managed downstream. That means incorporating site and patient insights earlier, pressure-testing eligibility assumptions and aligning screening workflows with the realities sites face every day.

The clinical trials that succeed in 2026 won’t just be the ones that recruit faster. They’ll be the ones that respect the full patient journey, from first touch through study completion and design accordingly.

Patient retention doesn’t always break down halfway through a study. More often, it breaks before enrollment even begins.