All patients with ICD-9 codes 430.XX to 438.XX will be administratively identified from starting January 1, 2000 and administratively pulled into a HealthTrac®-Stroke registry. Each patient included in the registry will undergo a validation process to ensure stroke type and event dates are accurate. Staff at CPCRS will manually review the electronic medical record for each patient in the registry to ensure the ICD-9 code for stroke is accurate according to detailed procedures (Appendix I). Patients with history that indicates transient ischemic attack, subarachnoid hemorrhage, intracerebral hemorrhage, or cardioembolic stroke will be coded as "TIA" or "Hemorrhage" or "Cardioembolic" stroke, respectively, in the registry and not eligible for study screening or entry. Patients will be considered to have ischemic stroke if there is documentation in the medical record, hospital discharge summary or otherwise, indicating the patient had symptoms consistent with a stroke, for example but not limited to sudden numbness or weakness of the face, arm or leg, especially on one side of the body, sudden confusion, trouble speaking or understanding, sudden trouble seeing in one or both eyes, sudden trouble walking, dizziness, loss of balance or coordination, sudden, severe headache with no known cause) and/or imaging (MRI or CT scan) of clinically relevant brain lesions or there is documentation from a physician noting the patient has had a stroke.12 It is estimated that approximately 5200 patients will have validated stroke, of which 4200 will have ischemic stroke (both cardioembolic and non-cardioembolic) and approximately 2500 will have non-cardioembolic ischemic stroke. All eligible patients with a validated non-cardioembolic ischemic stroke diagnosis in the HealthTrac®-Stroke registry will be screened for study eligibility by study personnel.