Dealing With a Deluge of Data: An Assessment of Adverse Event Data on North Central Cancer Treatment Group Trials

Purpose Adverse events (AEs) are monitored in clinical trials for patient safety, to satisfy reporting requirements, and develop safety profiles. Recently, much attention has been placed on the reporting of serious AEs (SAEs) that are either life threatening or lethal in clinical trials. However, SAEs comprise a small subset of all AE data collected for trials; the majority of AE data collected are routine AEs (RAEs) regarding non–life-threatening events. We assessed the utility of the RAE data collected, relative to the volume. Patients and Methods We surveyed the RAE data from 26 North Central Cancer Treatment Group coordinated trials. Results A total of 8,318 (11%) of 75,598 of RAEs required queries. Of these, 86% were protocol-required RAEs, 83% of RAEs required per protocol were within normal limits (eg, platelets) or not present, and 61% of extra AEs were mild. One fifth of RAEs were considered unlikely to be related or unrelated to treatment. Overall, 3% of events were severe, life threatening, or caused death. Only 1% of RAE data reported required expedited reporting (eg, via Adverse Event Expedited Reporting System). Results indicate that 72% of RAEs would be eliminated if only the maximum severity per patient and type were required. These results were validated in a large phase III trial. Conclusion The majority of RAEs identified, transcribed, and entered are not clinically important. Our data suggest that reducing the number of AEs monitored will affect substantially neither overall patient safety nor compromise evaluation of regimens undergoing testing. We present several considerations for such a reduction in data collection, as well as a policy that we have used to address the deluge of RAE data.