Impact of Protocol Amendment - Sponsor Report

PSI Wonderful Wednesday Visualisation Challenge - September 2026

Executive Summary

This report evaluates the impact of a clinical trial protocol amendment for a sponsor. During study conduct of a hypothetical Phase III clinical trial for a chronic disease, recruitment is slower than anticipated. A major protocol amendment is introduced at Month 10 to relax eligibility criteria, reduce visit frequency and simplify data collection requirements. The report focuses on three critical dimensions of trial performance: enrollment, quality, and costs. Our analysis compares metrics before the amendment (Months 1-9) and after the amendment (Months 10+) to determine whether the amendment successfully improved trial operations.

Background

The protocol amendment represents a significant operational change to the clinical trial. By comparing key performance indicators before and after Month 10, we can assess whether the amendment achieved its intended objectives and check for any unintended consequences on trial operations.

Data and Methods

Data was analyzed by comparing mean values of key performance indicators in two periods: Before Amendment (Months 1-9, n=9 months) and After Amendment (Months 10+, n=15 months). The protocol amendment was implemented at the beginning of Month 10.

Results

1. Enrollment Metrics

Enrollment is an important factor for trial success. We examined two indicators before and after protocol amendment: new subjects enrolled per active site and screen failure rate.

Figure 1: Before vs After Amendment - Enrollment Metrics

Key Findings:

  • New Subjects Enrolled: The amendment resulted in an increase in the average number of new subjects enrolled per site.

  • Screen failure rate: The average screen failure rate dropped after the protocol amendment.

These findings suggest that the amendment improved trial enrollment.

2. Quality Metrics

Trial quality reflects adherence to protocol and data quality. We examined protocol deviations per subject, average query resolution time and retention rate.

Figure 2: Before vs After Amendment - Quality Metrics

Key Findings:

  • Deviations per Subject: Per-subject deviation rate decreased after the protocol amendment, reflecting the quality impact adjusted for enrollment volume.

  • Average Query Days: Query resolution time decreased after protocol amendment.

  • Retention rate: The average retention rate was similar in the months before and after protocol amendment.

These findings indicate that the amendment improved trial integrity and data quality.

3. Cost Metrics

Trial efficiency also depends on managing operational costs and trial participant burden. We examined monitoring costs and visit burden.

Figure 3: Before vs After Amendment - Cost and Burden Metrics

Key Findings:

  • Monitoring Costs: Average monitoring costs decreased slightly after protocol amendment.
  • Visit burden: The visit burden decreased after protocol amendment.

These findings show a positive effect on visit burden for trial participants after the protocol amendment. While the monitoring costs decreased only slightly after protocol amendment, the costs might also have been impacted by increased enrollment numbers after the amendment.

Conclusion

The protocol amendment represented a substantive operational change to the clinical trial. Enrollment data shows a positive trend in participant recruitment following the amendment. Quality metrics also show improved data quality and integrity after the amendment. Further analysis could be performed to better understand the impact on monitoring costs. No unintended consequences on trial operations were identified from this analysis. The analysis results indicate that the protocol amendment was successful in improving trial performance.