Grading the severity of adverse events (AEs)

All AEs will be assessed by the investigator using the protocol-defined grading system. The use of a standard table for interpreting and grading abnormal signs, symptoms, and laboratory parameters is recommended. If the protocol has no defined grading system, or if the AE is not described in the existing grading system, the following guidelines should be used to qualify severity:

  • Grade 1: Mild — transient or mild discomfort (< 48 hours); no medical intervention/ therapy required.
  • Grade 2: Moderate — mild to moderate limitation in activity — some assistance may be needed; no or minimal medical intervention/ therapy required.
  • Grade 3: Severe — marked limitation in activity, some assistance usually required; medical intervention/ therapy required, hospitalization possible.
  • Grade 4: Life-Threatening — extreme limitation in activity; significant assistance required; significant medical intervention/therapy required, hospitalization, or hospice care probable.
  • Grade 5: Death.

For more information, see AE Decision Flowchart and SAE Reporting Flowchart. (Source: National Institute of Allergy and Infectious Diseases. International Centers For Tropical Disease Research Network (ICTDR) Investigator Manual: Monitoring And Reporting Adverse Events, Bethesda, MD; 2003.)