Evaluating Transportation and Accessibility in Clinical Site Feasibility

Introduction: Why Access and Travel Logistics Matter

Transportation and accessibility have become critical considerations in clinical trial site feasibility, especially as studies increasingly focus on patient-centric design and diversity in enrollment. A site that is difficult to reach—due to poor transit, long travel times, or geographic isolation—poses challenges for both subjects and clinical research associates (CRAs). It can lead to screen failures, missed visits, high dropout rates, and noncompliance with scheduled assessments.

To enhance recruitment and retention, feasibility assessments must incorporate structured evaluations of site accessibility. This article explores tools, metrics, and real-world data used to assess transportation and access-related risks in trial planning.

1. Dimensions of Site Accessibility

Accessibility assessments in feasibility go beyond geographic location and include:

• Proximity: Distance from major population clusters and healthcare facilities
• Public Transport Access: Availability and frequency of bus/train/metro lines
• Private Transport Routes: Road quality, traffic patterns, and parking availability
• Transport Cost Burden: Cost of reaching the site for follow-up visits
• Weather/Seasonal Barriers: Monsoon, snow, or heat wave effects on patient mobility
• CRA Travel Logistics: Feasibility of regular monitoring visits

2. Impact on Recruitment and Retention

Data consistently show that travel-related burden is a leading barrier to patient recruitment and retention:

• Patients traveling >90 minutes are 35% more likely to decline participation
• Out-of-pocket transport costs over $25 per visit increase dropout risk
• Sites without transit connections show higher visit nonadherence rates

Example: In a U.S. cardiology trial, 18% of eligible patients declined participation due to distance, and 29% of dropouts cited transportation as a factor.

3. Tools to Evaluate Site Accessibility During Feasibility

Modern feasibility assessments include structured tools such as:

• Accessibility Heatmaps: Overlay transit routes on catchment maps
• Google Maps API integration: Estimate average commute times by time of day
• Patient Persona Journey Mapping: Simulate travel from community to site
• Site Travel Questionnaire: Self-reported access, parking, and logistics infrastructure
• CRA Access Scorecard: Time/cost estimates for regular monitoring travel

4. Accessibility Scorecard Sample

The following scorecard was used in a decentralized feasibility analysis:

Sites scoring <60% were deprioritized due to travel-related risk to timelines and data integrity.

5. Planning for Patient-Centric Access

Sponsors are increasingly offering transport support to improve accessibility. Strategies include:

• Door-to-door patient transport via taxi or shuttle
• Prepaid fuel cards or mileage reimbursement
• Flexible scheduling around commute availability
• Use of local mobile clinics or community-based follow-ups
• Home health nursing to reduce site visit burden

Case Study: In a Parkinson’s study, mobile nursing support reduced patient dropouts by 45% across rural sites.

6. Accessibility and Regulatory Review

Though not often directly stated, regulators view accessibility as a component of ethical trial conduct and compliance with informed consent processes. IRBs/IECs have asked for clarification when:

• Patients from rural areas are expected to travel multiple times weekly
• Sites lack public transit for elderly patients in oncology studies
• Trials involve frequent procedures requiring sedation or overnight stays

Regulatory guidance increasingly favors decentralized components when transportation is a recruitment barrier.

7. CRA Accessibility: The Overlooked Element

Site monitoring is another function impacted by site accessibility:

• CRA retention suffers with excessive travel burdens
• Remote regions may cause delays in source verification or SDV
• Higher CRA travel costs affect budget allocation and feasibility ROI

CRA access feasibility should be reviewed alongside patient accessibility to ensure comprehensive risk mitigation.

8. Planning Tools and SOP Integration

Feasibility and operations teams should include travel and access parameters in:

• Site Feasibility Assessment Forms (SFAF)
• CTMS-based site evaluation templates
• Study-specific Monitoring Plans (SSMP)
• Subject Retention Plans

Accessibility should be logged and risk scored similar to timelines and enrollment capability during pre-initiation meetings.

Conclusion

Transportation and accessibility are no longer peripheral concerns in clinical trial design—they are central to operational success and ethical trial conduct. By evaluating and planning for site access challenges, sponsors can increase enrollment rates, improve patient satisfaction, reduce dropout, and comply with patient rights under GCP. Future trials must proactively integrate accessibility into site feasibility workflows and invest in support mechanisms to overcome logistical barriers.