According to the U.S. Food and Drug Administration's Center of Drug Evaluation and Research, the top five deficiency categories for site inspections caught by clinical monitors as reported in the 2001 Report to the Nation[5] are: Therefore, the primary goal of clinical trial monitoring is to observe each trial site to ensure that the standardized operation procedures for the trial are being followed, reporting and managing any deviations from the investigation plan as they occur.
[3][6] The FDA itself maintains an Adverse Event Reporting System for such occurrences in clinical trials it oversees in the United States.
[citation needed] Almost all field monitoring requires regular visits to the site by the clinical research associate throughout the period of the study.
[1] On occasion, an extremely simple, low-risk study might be monitored almost exclusively by telephone except for the startup and closeout visits.
[citation needed] The level of scrutiny of monitoring varies across studies based on risks and nature of the trial.