Top Barriers to Participation in Clinical Trials

Recruiting study participants is one of the most challenging tasks in the clinical trial process, and arguably one of the biggest barriers to success in clinical research.

Low enrollment is a chronic problem for many studies. According to an Applied Clinical Trial Stakeholder Survey, 19% of registered trials that closed or terminated either failed to meet accrual goals (85% of expected enrollment) or were terminated early due to insufficient accrual.

So, why is patient recruitment such a significant and ongoing challenge for research organizations? Understanding the various factors that influence an individuals decision to participate in a study can often help research professionals determine the root cause of enrollment problems. In this infographic, we explore the common barriers individuals face when deciding whether or not to participate in a clinical trial.

Misconceptions and a lack of awareness seem to be the most significant barriers for individuals who otherwise might be willing to participate in a clinical trial. It’s critical to address these barriers by spreading positive, community-forward information about clinical research and encouraging more industry stakeholders to participate in outreach efforts.

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Top Barriers to Participation in Clinical Trials

Why are Under-Enrolling Clinical Trials a Significant Problem?

The consequences of low accrual in clinical trials is significant on a number of levels, for all stakeholders – sites, sponsors, and participants. Some consequences include:

• Ethical implications
• Relinquish scientific validity
• Missed opportunities for participants
• Wasted time, resources, and funds

A 2021 CISCRP global study of over 11,000 participants captured the public perception of clinical research, including general perception of clinical research and possible barriers of participating or continuing on with a study.

Importance of Clinical Studies¹

Overall, 76% of survey participants felt clinical research is “very important” when discovering and developing new medicine or therapy treatments. However, there are still concerns over participating in a study. Respondents indicated the top risks included:

• Suffering from a side effect
• Risking overall health
• Stopping current and effective treatments

Making Informed Consent Forms Understandable

A challenge for many research staff is creating an informed consent in lay terms so participants can accurately understand and interpret the information given to them. When asking study volunteers themselves²,

• 57% reported it’s important to receive overall research study results presented or explained in easy-to-understand language
• 54% said it’s important for research staff to give clinical trial results in simple language

To ensure consent form understanding, it’s critical for research staff to review the form with participants and ensure understanding throughout the entire document.

• 46% of participants said they reviewed with the study coordinator or research nurse
• 28% of participants said they reviewed with the principal investigator or study doctor ²

Common Participation Burdens, Reasons for Drop Out

Why do participants drop out of studies ³

• Poor communication with the study center: 18%
• The location of the study center: 18%
• The study drug’s side effects: 16%
• “Cumbersome” study visit procedures: 16%

Travel is also a top participation burden

Survey results found 25% of respondents said they travel over an hour one way for every visit they have at a clinic. The amount of tasks participants needed to engage in during in-person visits also became burdensome. Respondents reported the following tasks most burdensome ³:

• Traveling to the study clinic: 44% 
• Undergoing a diagnostic test: 42% 
• Study visit length: 40% 
• Getting lab work done: 38% 
• Completing a health questionnaire: 32% 

Even though these may be burdensome reasons, there are ways to make the study less disruptive, including:

• Making study visits virtual: 38% 
• Reduced travel times and distances: 32% 
• Enabling at-home visits from a study nurse or doctor: 31% 
• Receiving help or assistance when traveling to and from the clinic: 24% 

Additionally, 27% indicated receiving a pre-paid debit card for any study-related expense incurred would make the study less disruptive. This may be due to:

• 50% receiving compensation for their time 
• 26% receiving reimbursement via cash or check for any out-of-pocket expenses 

Data accurate as of November 2021

Sources: 

1: https://www.ciscrp.org/wp-content/uploads/2021/11/2021-PI-General-Perceptions-Report-04NOV2021-FINAL.pdf 

2: https://www.ciscrp.org/wp-content/uploads/2021/11/2021-PI-Engagement-Preferences-Report-04NOV2021-FINAL.pdf  

3: https://www.ciscrp.org/wp-content/uploads/2021/11/2021-PI-Participation-Experience-Report-04NOV2021-FINAL.pdf  

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