Clinical trial participants travel 67 miles to study sites on average, analysis finds

The analysis found participants in the dataset traveled 67 miles one way on average to visit clinical trial sites this year. An earlier study, which looked at data on University of California San Francisco patients who enrolled in cancer clinical trials between 1993 and 2014, found the average distance traveled to be 25.8 miles. 

Greenphire found rare disease patients, who are treated at specialist centers and by definition are found at low concentrations, travel particularly long distances to clinical trial sites. On average, the rare disease patients in the Greenphire dataset traveled 135 miles to their clinical trial sites in 2022.

If Greenphire’s figures represent a truer reflection of the travel burden than the earlier study, it suggests that a key barrier to recruitment and retention of clinical trial participants may be a bigger problem than previously thought.

A separate survey by the Center for Information and Study on Clinical Research Participation, which was sponsored by Greenphire, provided evidence that the burden travel places on patients has increased in recent years.

The survey, the findings of which were first published early this year, found that clinical trial travel has become more burdensome, rising from 29% in 2019 to 44% in 2021. Sixty percent of trial participants had to travel more than 30 minutes one way to get to the study clinic.

Historically, sponsors had limited power to address the travel burden beyond covering costs and trying to reduce the number of site visits. The validation of digital technologies that enable remote data capture and televisits has provided the industry with more ways to reduce travel and enabled hybrid clinical trials that are favored by many patients.

In the survey, 81% of respondents cited a preference for a hybrid model. Another survey, conducted in Europe by James Lind Care, found 57% of people prefer participating mostly from home with only a few site visits.