What methods of measurement are available for calculating TTR for people taking vitamin K antagonists?
When calculating TTR for people taking vitamin K antagonists, a validated method of measurement, such as the Rosendaal method for computer-assisted dosing or proportion of tests in range for manual dosing, should be used. In addition, measurements taken during the first 6 weeks of treatment should be excluded, and TTR should be calculated over a maintenance period of at least 6 months.