How many studies should a site run at once?

Why is there no standard number?

Because studies differ enormously. Tufts CSDD data shows the average Phase III trial grew from 187 to 301 procedures between 2020 and 2025 (Bourne Partners, citing Tufts CSDD), and total procedures are up 61% versus ten years ago (SCRS via Clinical Leader). One complex oncology study can consume more time than three simple observational ones.

How do you calculate your capacity?

1. Count available hours per coordinator per month, minus administration.
2. Estimate each study's monthly hours: visits times average visit length, plus data entry, query resolution, monitoring visits, and regulatory upkeep.
3. Add training: an average of 17.5 hours per study per month (SCRS).
4. Add recruitment time for studies still enrolling.
5. Compare the total with available hours, leaving buffer for surprises.

When do studies compete with each other?

When two protocols target the same patients. Overlapping studies split your patient pool and can mean neither enrolls well. In a typical trial 11% of sites enroll no patients (Tufts CSDD); taking a study you cannot fill is a common way to become one of them.

What are the warning signs of overload?

• Data entry falling behind sponsor windows.
• Rising protocol deviations or monitoring findings.
• Staff working evenings to keep up, a path to turnover that runs 35% to 61% a year at sites (SCRS).
• Open studies with no enrollment.

How do sites add capacity safely?

Cross train staff, decline studies that overlap heavily, and move recruitment work out of coordinators' hours. Sites at SCRS stressed shifting staff toward enrollment as studies open (Bourne Partners). Physician outreach that runs as a system, rather than as coordinator phone calls, is one of the easiest pieces to take off their plate. See why coordinators leave.