# The Grand Divergence: 25-Year History

In the history of clinical research, has the volume gap between Africa and high-income regions widened or narrowed over twenty-five years of trial registration? This longitudinal analysis tracked trial volumes across five epochs from 2000 to 2025 using ClinicalTrials.gov first-posted-date metadata for Africa and comparator regions. Africa grew from 678 trials in 2000-2005 to 11,599 in 2021-2025, while the United States grew from 16,409 to 48,234. Africa's 17x absolute growth outpaced the United States 2.9x growth, but the absolute gap widened from 15,731 to 36,635 trials. The 2005 ICMJE mandate requiring trial registration for journal publication triggered exponential European growth that Africa never matched proportionally. These findings reveal a grand divergence where proportional equity is receding despite absolute growth. Interpretation is limited by retrospective registration of older trials which may distort early-epoch counts.

## References

1. Alemayehu C, et al. "Behind the mask of the African clinical trials landscape." Trials. 2018;19:519.
2. Drain PK, et al. "Global migration of clinical trials." Nat Rev Drug Discov. 2018;17:765-766.

## Note Block

- Type: research
- App: https://mahmood726-cyber.github.io/africa-e156-students/health-disease/dashboards/grand-divergence.html
- Code: https://github.com/mahmood726-cyber/africa-e156-students/blob/master/health-disease/code/grand-divergence.py
- Data: ClinicalTrials.gov API v2
- Date: 2026-04-05