Improving Patient Recruitment & Retention in Clinical Trials

Improving Patient Recruitment & Retention in Clinical Trials | QbD Group

7:54

In clinical research, the success of a trial heavily depends on two key factors: recruiting enough eligible participants and retaining them throughout the study. While this may sound simple in theory, in practice, it’s one of the most resource-intensive and challenging aspects of trial execution.

In this blog post, we explore:

Why patient enrolment and retention are critical to study success
Practical strategies to improve recruitment
How to enhance retention through patient-focused trial design
And how QbD Group can support you throughout the process

Let’s take a closer look at each of these areas.

Why Are Patient Enrolment and Retention So Important?

The number of patients needed in a trial is defined by statistical power calculations that take into account the trial’s objectives, the expected effect size, and the confidence level required. Under-recruitment or high dropout rates can compromise statistical validity, introduce bias, and ultimately prevent regulatory approval of a new treatment.

In addition to scientific concerns, poor recruitment or high attrition can cause delays and inflate budgets—particularly if additional sites need to be opened or recruitment periods extended. Given the costs associated with infrastructure, staff, and patient reimbursements, failing to meet targets often translates to wasted resources and missed opportunities.

Strategies to Improve Patient Recruitment

The following strategies could be considered to achieve the required patient recruitment targets in clinical research studies:

1. Define Clear Eligibility Criteria

Patient recruitment can be streamlined by defining clear eligibility criteria. This ensures that only the most suitable patients are considered for the trial.

This way, site teams can focus on screening patients who are more likely to meet the trial requirements, reducing the time spent screening and, in some cases, even recruiting unsuitable candidates.

Moreover, screening patients based on well-defined eligibility criteria reduces variability, leading to improved study validity and more reliable results.

2. Engage and Train Site Investigators

Motivated and well-informed site teams are critical for achieving recruitment targets. Effective strategies include:

Comprehensive protocol training on the trial protocol and eligibility criteria to avoid protocol deviations and streamline screening
Investigator meetings to provide important progress updates and allow knowledge sharing between sites. Investigator meetings are a good tool to remind sites about the trial and re-motivate site teams to actively participate in the trial.
Practical materials:
- Pocket cards with eligibility criteria
- Sheets where the screening process is clearly presented – these can be very useful to be placed at nursing stations, physicians’ desk or site’s clinical trials centre/office
- Posters in staff rooms – these can be used to remind site staff about checking whether their patients are eligible for the trial
- Trial branded pens or other office supplies
Scientific or professional incentives, including co-authorship and acknowledgements, to encourage active participation

3. Enhance Patient Engagement

Patients make the final decision to participate, so their needs and understanding must be prioritized:

Provide clear and accessible information

Use lay-friendly materials to explain the purpose and procedures of the trial.
Involve patient representatives in the development of patient-facing documents to ensure clarity and avoid confusion.
Go beyond simply handing out information sheets—take time to verbally explain the trial and confirm patient understanding.
In case of a language barrier, use a professional interpreter to avoid excluding certain patient groups.
Share post-trial updates in an accessible format (e.g., via the study physician, poster, or leaflet in the waiting room) to keep participants informed and valued.
Thank patients and caregivers with a postcard or similar token at the end of study participation to foster a sense of belonging and appreciation.

Raise awareness through onsite materials

Place posters or leaflets with key trial information in patient waiting rooms or hospital wards.
This allows patients to learn about ongoing studies and initiate a conversation with site staff if interested.

Adapt consent procedures to the target population

Choose methods that suit the patient group—for example, avoid e-consent for elderly populations who may lack access to digital devices.
Provide age-appropriate information sheets and assent forms when involving paediatric patients.

Consider appropriate financial incentives

Offer compensation—such as gift vouchers or direct transfers—to acknowledge the time and effort patients invest by participating in the trial.

It’s crucial that patients never feel pressured to join a trial. Sufficient time, space for questions, and external consultation should always be part of the decision-making process.

Remember: all patient-facing materials must be reviewed by an Independent Ethics Committee.

Strategies to Improve Patient Retention

1. Involve Patient Representatives Early

Involving patient groups during the trial design phase can help create more patient-friendly protocols, improving retention.

2. Make Follow-Up Easier

Address logistical barriers by:

Understanding Standard of Care patient hospital paths and mimic the flow in the protocol schedule of assessments
Offering home visits, where appropriate
Scheduling appointments during evenings or weekends
Sending paper questionnaires with return envelopes and reminders
Providing alternatives, such as phone-based follow-ups

3. Reimburse Travel and Related Costs

Covering transportation or other expenses helps reduce the burden of participation, especially for patients traveling specifically for trial visits.

4. Maintain Active Communication

Proactive reminders by email, SMS, or phone calls can reduce missed visits. Offering flexible ways to complete tasks—like phone questionnaires—can also boost participation.

5. Keep Patients Informed

Trial websites, newsletters, or dedicated portals help keep patients informed, engaged and show that their contribution is valued.

6. Collect and Use Patient Feedback

Feedback gathered through trusted healthcare providers can help improve future trials and increase retention.

How QbD Group Can Support Patient Recruitment and Retention

At QbD Clinical, we combine regulatory expertise with operational excellence to help sponsors run successful trials—on time and within budget.

Our multidisciplinary team of regulatory specialists, safety managers, medical writers, clinical project managers, and CRAs work closely together to support your recruitment and retention strategy. Here’s how we can help: