: The long-term goal of this research is to improve health outcomes in patients on chronic oral anticoagulation therapy. My primary aim is to determine the impact on INR control resulting from the integration of information on patient health literacy and numeracy, health knowledge and health beliefs regarding warfarin therapy into the clinical information provided to the pharmacist. The central hypothesis of this research is that by expanding the clinical information available to incorporate information pertaining to patients' health literacy and numeracy, health knowledge and health beliefs, clinicians will be able to tailor educational interventions and decision-making to best fit the patients' needs. To test the central hypothesis, the proposed study will address the following three aims: (1) To determine if patient health knowledge, health beliefs, and health literacy and numeracy of warfarin therapy, when integrated into pharmacists' clinical information, will impact patients INR control. (2) To determine if patient health knowledge, health beliefs, and health literacy and numeracy of warfarin, when integrated into pharmacists' clinical information, will impact patient's knowledge of oral anticoagulation therapy. (3) To determine the cost implications resulting from the additional process of collecting, analyzing and incorporating information on patient health knowledge, health beliefs, and health literacy and numeracy regarding warfarin therapy.