# Calculate Incidence Rates for adverse event occurrences

Use this option to compute the rate of occurrence in patient years for adverse events whose occurrence starts within a specified time at risk period (either Patient Years of Exposure or Patient Years on Study). This option is enabled only when you choose to count multiple occurrences of an event per subject report option.

When checked, you must also choose your type of Time at Risk: and a Patient Years Multiplier: and select to either determine time at risk and event inclusion based on dates available in the DM or ADSL data (representing either treatment start/end or study start/end) or based on derived time and flag variables in the DM/ADSL data sets (for each patient's time at risk) and an inclusion flag (if the AE record should be considered in the rate calculation).

Note, when this option is checked, events that occurred within the time at risk period only are shown in the report. A new column named "IR" is inserted into the table representing the incidence rates for each adverse event. Additionally the counts graph can be changed to show Incidence Rates instead of counts. A new column "Overall Incidence Rate" will be calculated and available in the data filter for use to filter to common events that occur at a higher rate (for example).

When this option is checked, patient years for demographic groups will be listed underneath the demographic group heading in the results tables.

Note: The incidence rates are completely dynamic and will be automatically recalculated to reflect any subject filter or subpopulation that is selected with the data filter.

### To Specify this Option:

| 8 | Make sure that the Count multiple occurrences of an event per subject box is checked.

| 8 | Click the check box.