Recruiting and retaining participants for clinical trials present significant challenges, often leading to delays and increased costs. Key statistics highlighting these difficulties include:

• Trial Delays Due to Recruitment Issues: Approximately 80% of clinical trials are delayed or closed because of problems with recruitment.

• Extended Timelines: Nine out of ten trials ultimately double their original timeline to meet enrollment goals.

• Underperforming Sites: Nearly half of all clinical trial sites under-enroll, and in some cases, 11% of sites fail to enroll a single patient.

• Participant Awareness: A 2020 study found that 41% of U.S. adults were unaware of clinical trials, and only 8.9% reported being invited to participate, with less than half of those invited eventually enrolling.

Regarding costs:

• Per-Patient Recruitment Costs: The average per-patient cost in the late 2000s was about $5,500 for a Phase I trial; $6,500 for a Phase II trial; and more than $7,600 for a Phase III trial.

• Cost of Patient Dropouts: Patient retention is critical to the success of a clinical study, and the true cost of patient drop-outs goes far beyond the cost of patient recruitment.

These figures underscore the importance of effective recruitment and retention strategies to mitigate delays and control costs in clinical trials.