Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Incidence rate of stroke/transient ischemic attack (TIA) during initial vitamin K antagonist (VKA) treatment by time since atrial fibrillation (AF) diagnosis. PY indicates person‐years; Incidence rate (IR) of stroke/TIA during VKA treatment were calculated per month since AF diagnosis. IR function by time since AF was fitted using quadratic splines and weighting for variances of the estimated IRs.
