Couzin-Frankel J. Researchers seek clear reasons when clinical trials end early. Science July 2015;349(6245):222
About 12% of clinical trials are reported to shut down prematurely. Knowing why could help minimize the number of terminated trials going forward. A team of three computational biologists began exploring why clinical trials end prematurely. They looked at all 3122 terminated trials on the ClinicalTrials.gov registry at the time their study began, and divided the reasons for ending early into "buckets," such as funding, ethical reasons, or business decisions, so they could see the breakdown by category. but those explanations were often hazy.