Why isn’t SDARR equal to SDRR when I run HRV analysis on a 5 minute block of data?

SDARR is the standard deviation of the set of averaged RR intervals; this averaging period is typically 5 minutes. If the entire sample period is 5 minutes, you will have a set containing precisely one averaged RR interval. The standard deviation of a set containing one element is always 0.


Note: The default averaging period is 5 minutes. This can be altered in the HRV Settings dialogue “SDARR” averaging text box (see image below).





















For further assistance with this topic, please contact your local Technical Support Representative by completing the online form located HERE.